diff --git a/Applications/FileIO/TetGenInterface.cpp b/Applications/FileIO/TetGenInterface.cpp
index 09ff26c2ad0ee8661660140ca8a96f31ff03fc17..133245369a10cbbb68526ab1338ea8458edb615f 100644
--- a/Applications/FileIO/TetGenInterface.cpp
+++ b/Applications/FileIO/TetGenInterface.cpp
@@ -293,7 +293,7 @@ bool TetGenInterface::readNodesFromStream (std::ifstream &ins,
     return false;
 }
 
-bool TetGenInterface::parseNodesFileHeader(std::string& line,
+bool TetGenInterface::parseNodesFileHeader(std::string const& line,
                                            std::size_t& n_nodes,
                                            std::size_t& dim,
                                            std::size_t& n_attributes,
diff --git a/Applications/FileIO/TetGenInterface.h b/Applications/FileIO/TetGenInterface.h
index 690fece898f123f4f24a9cb5cb06760ff9b86b9b..7b8eca28e52c8d9a5880db5bae7da3fc6c553188 100644
--- a/Applications/FileIO/TetGenInterface.h
+++ b/Applications/FileIO/TetGenInterface.h
@@ -122,7 +122,7 @@ private:
      * @param boundary_markers  have the nodes boundary information (output)
      * @return true, if the file header is read, false if the method detects an error
      */
-    static bool parseNodesFileHeader(std::string& line,
+    static bool parseNodesFileHeader(std::string const& line,
                                      std::size_t& n_nodes,
                                      std::size_t& dim,
                                      std::size_t& n_attributes,
diff --git a/Applications/Utils/MeshEdit/CreateBoundaryConditionsAlongPolylines.cpp b/Applications/Utils/MeshEdit/CreateBoundaryConditionsAlongPolylines.cpp
index a481b08ea1c5974449cbd95595ff8bd65b542030..ed3682d203fa307db77e6d2ac084b3288d090a9c 100644
--- a/Applications/Utils/MeshEdit/CreateBoundaryConditionsAlongPolylines.cpp
+++ b/Applications/Utils/MeshEdit/CreateBoundaryConditionsAlongPolylines.cpp
@@ -85,8 +85,8 @@ void writeLiquidFlowPointBC(std::ostream & bc_out, std::string const& pnt_name)
 // set on, geo_name is the name the geometry can be accessed with, out_fname is
 // the base file name the gli and bc as well as the gml file will be written to.
 void writeBCsAndGeometry(GeoLib::GEOObjects& geometry_sets,
-                         std::string& geo_name, std::string const& out_fname,
-                         std::string const& bc_type, bool write_gml)
+                         std::string const& geo_name, std::string const& out_fname,
+                         std::string const& bc_type, bool const write_gml)
 {
     if (write_gml) {
         INFO("write points to '{:s}.gml'.", geo_name);
diff --git a/Applications/Utils/MeshEdit/swapNodeCoordinateAxes.cpp b/Applications/Utils/MeshEdit/swapNodeCoordinateAxes.cpp
index 67f3ba7ecea32c48065bd675060103026e595558..3fd895d738fd7541c76c81f8f0a1025ba0ac1507 100644
--- a/Applications/Utils/MeshEdit/swapNodeCoordinateAxes.cpp
+++ b/Applications/Utils/MeshEdit/swapNodeCoordinateAxes.cpp
@@ -22,7 +22,8 @@
 #include "MeshLib/IO/readMeshFromFile.h"
 #include "MeshLib/IO/writeMeshToFile.h"
 
-static void swapNodeCoordinateAxes(MeshLib::Mesh &mesh, std::array<int, 3> const& new_axes_indices)
+static void swapNodeCoordinateAxes(MeshLib::Mesh const& mesh,
+                                   std::array<int, 3> const& new_axes_indices)
 {
     double new_coords[3] = {};
     for (MeshLib::Node* node : mesh.getNodes())
diff --git a/Applications/Utils/ModelPreparation/PartitionMesh/NodeWiseMeshPartitioner.cpp b/Applications/Utils/ModelPreparation/PartitionMesh/NodeWiseMeshPartitioner.cpp
index dea72ae4a19ccee034611539b725cb8d2f406376..1f62801d481e648c2dc292773b15285c51496906 100644
--- a/Applications/Utils/ModelPreparation/PartitionMesh/NodeWiseMeshPartitioner.cpp
+++ b/Applications/Utils/ModelPreparation/PartitionMesh/NodeWiseMeshPartitioner.cpp
@@ -381,7 +381,7 @@ bool copyPropertyVector(
     MeshLib::Properties& partitioned_properties,
     std::vector<Partition> const& partitions,
     MeshLib::PropertyVector<T> const* const pv,
-    std::map<MeshLib::MeshItemType, std::size_t> const total_number_of_tuples)
+    std::map<MeshLib::MeshItemType, std::size_t> const& total_number_of_tuples)
 {
     if (pv == nullptr)
     {
diff --git a/ChemistryLib/PhreeqcIO.cpp b/ChemistryLib/PhreeqcIO.cpp
index 3155ed8c1fbfc345923af07e8bfa611e7dff7644..2cba14a75706ab8a212a353370106c18daead5dd 100644
--- a/ChemistryLib/PhreeqcIO.cpp
+++ b/ChemistryLib/PhreeqcIO.cpp
@@ -128,7 +128,7 @@ static double averageReactantMolality(
 }
 }  // namespace
 
-PhreeqcIO::PhreeqcIO(std::string const project_file_name,
+PhreeqcIO::PhreeqcIO(std::string const& project_file_name,
                      std::string&& database,
                      std::unique_ptr<ChemicalSystem>&& chemical_system,
                      std::vector<ReactionRate>&& reaction_rates,
diff --git a/ChemistryLib/PhreeqcIO.h b/ChemistryLib/PhreeqcIO.h
index 1e9d189ba94e0804376381c11f395e62eb6bbf2f..be513a73635ee3b4b666cc57a64dfa6de462b1d4 100644
--- a/ChemistryLib/PhreeqcIO.h
+++ b/ChemistryLib/PhreeqcIO.h
@@ -34,7 +34,7 @@ struct UserPunch;
 class PhreeqcIO final : public ChemicalSolverInterface
 {
 public:
-    PhreeqcIO(std::string const project_file_name,
+    PhreeqcIO(std::string const& project_file_name,
               std::string&& database,
               std::unique_ptr<ChemicalSystem>&& chemical_system,
               std::vector<ReactionRate>&& reaction_rates,
diff --git a/MaterialLib/FractureModels/CreateCohesiveZoneModeI.cpp b/MaterialLib/FractureModels/CreateCohesiveZoneModeI.cpp
index ab2d844729336a62c502e45fef6bb3260b2beeff..2c74cfa633b64a3be0bc73dad3e840046dda261f 100644
--- a/MaterialLib/FractureModels/CreateCohesiveZoneModeI.cpp
+++ b/MaterialLib/FractureModels/CreateCohesiveZoneModeI.cpp
@@ -28,19 +28,19 @@ std::unique_ptr<FractureModelBase<DisplacementDim>> createCohesiveZoneModeI(
     config.checkConfigParameter("type", "CohesiveZoneModeI");
     DBUG("Create CohesiveZoneModeI material");
 
-    auto& Kn = ParameterLib::findParameter<double>(
+    auto const& Kn = ParameterLib::findParameter<double>(
         //! \ogs_file_param_special{material__fracture_model__CohesiveZoneModeI__normal_stiffness}
         config, "normal_stiffness", parameters, 1);
 
-    auto& Ks = ParameterLib::findParameter<double>(
+    auto const& Ks = ParameterLib::findParameter<double>(
         //! \ogs_file_param_special{material__fracture_model__CohesiveZoneModeI__shear_stiffness}
         config, "shear_stiffness", parameters, 1);
 
-    auto& Gc = ParameterLib::findParameter<double>(
+    auto const& Gc = ParameterLib::findParameter<double>(
         //! \ogs_file_param_special{material__fracture_model__CohesiveZoneModeI__fracture_toughness}
         config, "fracture_toughness", parameters, 1);
 
-    auto& t_np = ParameterLib::findParameter<double>(
+    auto const& t_np = ParameterLib::findParameter<double>(
         //! \ogs_file_param_special{material__fracture_model__CohesiveZoneModeI__peak_normal_traction}
         config, "peak_normal_traction", parameters, 1);
 
diff --git a/MaterialLib/FractureModels/CreateLinearElasticIsotropic.cpp b/MaterialLib/FractureModels/CreateLinearElasticIsotropic.cpp
index 7c78eb3b2469d50a901eb8e0fae3c0687e09ef24..e420688ee43428aca090a0a698118cb624994598 100644
--- a/MaterialLib/FractureModels/CreateLinearElasticIsotropic.cpp
+++ b/MaterialLib/FractureModels/CreateLinearElasticIsotropic.cpp
@@ -27,11 +27,11 @@ createLinearElasticIsotropic(
     config.checkConfigParameter("type", "LinearElasticIsotropic");
     DBUG("Create LinearElasticIsotropic material");
 
-    auto& Kn = ParameterLib::findParameter<double>(
+    auto const& Kn = ParameterLib::findParameter<double>(
         //! \ogs_file_param_special{material__fracture_model__LinearElasticIsotropic__normal_stiffness}
         config, "normal_stiffness", parameters, 1);
 
-    auto& Ks = ParameterLib::findParameter<double>(
+    auto const& Ks = ParameterLib::findParameter<double>(
         //! \ogs_file_param_special{material__fracture_model__LinearElasticIsotropic__shear_stiffness}
         config, "shear_stiffness", parameters, 1);
 
diff --git a/MeshGeoToolsLib/BoundaryElementsAlongPolyline.cpp b/MeshGeoToolsLib/BoundaryElementsAlongPolyline.cpp
index 7e984d237be64faafedfc333a37ee93682ad0bff..6c5b3362d73bfa69120aed73a8acaaa824b966a9 100644
--- a/MeshGeoToolsLib/BoundaryElementsAlongPolyline.cpp
+++ b/MeshGeoToolsLib/BoundaryElementsAlongPolyline.cpp
@@ -32,7 +32,7 @@ BoundaryElementsAlongPolyline::BoundaryElementsAlongPolyline(
     auto node_ids_on_poly = mshNodeSearcher.getMeshNodeIDs(ply);
     MeshLib::ElementSearch es(_mesh);
     es.searchByNodeIDs(node_ids_on_poly);
-    auto& ele_ids_near_ply = es.getSearchedElementIDs();
+    auto const& ele_ids_near_ply = es.getSearchedElementIDs();
 
     // check all edges of the elements near the polyline
     for (auto ele_id : ele_ids_near_ply)
diff --git a/MeshGeoToolsLib/MeshNodesAlongSurface.cpp b/MeshGeoToolsLib/MeshNodesAlongSurface.cpp
index 46ffd36be013ccbd077a4f87d26a23007cd7c70f..bafc4c2548641727d6d589ee86ddeea90bcd947d 100644
--- a/MeshGeoToolsLib/MeshNodesAlongSurface.cpp
+++ b/MeshGeoToolsLib/MeshNodesAlongSurface.cpp
@@ -28,7 +28,7 @@ MeshNodesAlongSurface::MeshNodesAlongSurface(MeshLib::Mesh const& mesh,
                                              SearchAllNodes search_all_nodes)
     : _mesh(mesh), _sfc(sfc)
 {
-    auto& mesh_nodes = _mesh.getNodes();
+    auto const& mesh_nodes = _mesh.getNodes();
     const std::size_t n_nodes(search_all_nodes == SearchAllNodes::Yes
                                   ? _mesh.getNumberOfNodes()
                                   : _mesh.getNumberOfBaseNodes());
diff --git a/ProcessLib/ComponentTransport/ComponentTransportFEM.h b/ProcessLib/ComponentTransport/ComponentTransportFEM.h
index b117cab62802e0289a9e896a488d30b738b3f4f5..f6ef6990f2173722292c44f9d36f3393e45e643e 100644
--- a/ProcessLib/ComponentTransport/ComponentTransportFEM.h
+++ b/ProcessLib/ComponentTransport/ComponentTransportFEM.h
@@ -185,7 +185,7 @@ public:
         bool is_axially_symmetric,
         unsigned const integration_order,
         ComponentTransportProcessData const& process_data,
-        std::vector<std::reference_wrapper<ProcessVariable>>
+        std::vector<std::reference_wrapper<ProcessVariable>> const&
             transport_process_variables)
         : _element(element),
           _process_data(process_data),
diff --git a/ProcessLib/Output/Output.cpp b/ProcessLib/Output/Output.cpp
index 827191021707712fe943eb88092e3e1a50626855..8c56b48edcc2380635fc41c150cf6f10f5985777 100644
--- a/ProcessLib/Output/Output.cpp
+++ b/ProcessLib/Output/Output.cpp
@@ -302,7 +302,7 @@ void Output::doOutputAlways(Process const& process,
         return;
     }
 
-    auto output_bulk_mesh = [&](MeshLib::Mesh& mesh) {
+    auto output_bulk_mesh = [&](MeshLib::Mesh const& mesh) {
         MeshLib::IO::PVDFile* pvd_file = nullptr;
         if (_output_file_type == ProcessLib::OutputType::vtk)
         {
diff --git a/ProcessLib/PhaseField/CreatePhaseFieldProcess.cpp b/ProcessLib/PhaseField/CreatePhaseFieldProcess.cpp
index 398b7b81378c70994112884aa0166e61e217111e..98c4f8d0a72d38279afc773d081b06494575a4cb 100644
--- a/ProcessLib/PhaseField/CreatePhaseFieldProcess.cpp
+++ b/ProcessLib/PhaseField/CreatePhaseFieldProcess.cpp
@@ -112,42 +112,42 @@ std::unique_ptr<Process> createPhaseFieldProcess(
         config.getConfigSubtree("phasefield_parameters");
 
     // Residual stiffness
-    auto& residual_stiffness = ParameterLib::findParameter<double>(
+    auto const& residual_stiffness = ParameterLib::findParameter<double>(
         phasefield_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__PHASE_FIELD__phasefield_parameters__residual_stiffness}
         "residual_stiffness", parameters, 1);
     DBUG("Use '{:s}' as residual stiffness.", residual_stiffness.name);
 
     // Crack resistance
-    auto& crack_resistance = ParameterLib::findParameter<double>(
+    auto const& crack_resistance = ParameterLib::findParameter<double>(
         phasefield_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__PHASE_FIELD__phasefield_parameters__crack_resistance}
         "crack_resistance", parameters, 1);
     DBUG("Use '{:s}' as crack resistance.", crack_resistance.name);
 
     // Crack length scale
-    auto& crack_length_scale = ParameterLib::findParameter<double>(
+    auto const& crack_length_scale = ParameterLib::findParameter<double>(
         phasefield_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__PHASE_FIELD__phasefield_parameters__crack_length_scale}
         "crack_length_scale", parameters, 1);
     DBUG("Use '{:s}' as crack length scale.", crack_length_scale.name);
 
     // Kinetic coefficient
-    auto& kinetic_coefficient = ParameterLib::findParameter<double>(
+    auto const& kinetic_coefficient = ParameterLib::findParameter<double>(
         phasefield_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__PHASE_FIELD__phasefield_parameters__kinetic_coefficient}
         "kinetic_coefficient", parameters, 1);
     DBUG("Use '{:s}' as kinetic coefficient.", kinetic_coefficient.name);
 
     // Solid density
-    auto& solid_density = ParameterLib::findParameter<double>(
+    auto const& solid_density = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__PHASE_FIELD__solid_density}
         "solid_density", parameters, 1);
     DBUG("Use '{:s}' as solid density parameter.", solid_density.name);
 
     // History field
-    auto& history_field = ParameterLib::findParameter<double>(
+    auto const& history_field = ParameterLib::findParameter<double>(
         phasefield_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__PHASE_FIELD__phasefield_parameters__history_field}
         "history_field", parameters, 1);
diff --git a/ProcessLib/PhaseField/PhaseFieldProcessData.h b/ProcessLib/PhaseField/PhaseFieldProcessData.h
index 6dc06f20979471d10e2cf05beb95eb35631a80a7..c7354455923eed9481341dcf57ddc83ca10fcc86 100644
--- a/ProcessLib/PhaseField/PhaseFieldProcessData.h
+++ b/ProcessLib/PhaseField/PhaseFieldProcessData.h
@@ -43,7 +43,7 @@ struct PhaseFieldProcessData
     ParameterLib::Parameter<double> const& crack_length_scale;
     ParameterLib::Parameter<double> const& kinetic_coefficient;
     ParameterLib::Parameter<double> const& solid_density;
-    ParameterLib::Parameter<double>& history_field;
+    ParameterLib::Parameter<double> const& history_field;
     Eigen::Matrix<double, DisplacementDim, 1> const specific_body_force;
     bool propagating_crack = false;
     bool crack_pressure = false;
diff --git a/ProcessLib/Process.cpp b/ProcessLib/Process.cpp
index 051b311a24eb5fab644be619ca699f14409cd44e..60f58a75a6b5eb1e4bf3ec842450abdc179aed03 100644
--- a/ProcessLib/Process.cpp
+++ b/ProcessLib/Process.cpp
@@ -110,7 +110,7 @@ void Process::initialize()
 
 void Process::setInitialConditions(
     std::vector<GlobalVector*>& process_solutions,
-    std::vector<GlobalVector*>& process_solutions_prev,
+    std::vector<GlobalVector*> const& process_solutions_prev,
     double const t,
     int const process_id)
 {
diff --git a/ProcessLib/Process.h b/ProcessLib/Process.h
index 66e97859f8b4d0660e0051c4710811abadc8b626..c8026db328ed8938b2532ecf506b5c65cf64519e 100644
--- a/ProcessLib/Process.h
+++ b/ProcessLib/Process.h
@@ -84,7 +84,7 @@ public:
 
     void setInitialConditions(
         std::vector<GlobalVector*>& process_solutions,
-        std::vector<GlobalVector*>& process_solutions_prev,
+        std::vector<GlobalVector*> const& process_solutions_prev,
         double const t,
         int const process_id);
 
diff --git a/ProcessLib/ProcessVariable.cpp b/ProcessLib/ProcessVariable.cpp
index 22ca5a108db7ae408a6153225767cb02016253f8..bb59622fcfc1a8916d0fb7d3c37933a3115da78d 100644
--- a/ProcessLib/ProcessVariable.cpp
+++ b/ProcessLib/ProcessVariable.cpp
@@ -331,7 +331,7 @@ std::vector<std::unique_ptr<SourceTerm>> ProcessVariable::createSourceTerms(
     std::vector<std::unique_ptr<SourceTerm>> source_terms;
 
     transform(cbegin(_source_term_configs), cend(_source_term_configs),
-              back_inserter(source_terms), [&](auto& config) {
+              back_inserter(source_terms), [&](auto const& config) {
                   return createSourceTerm(config, dof_table, config.mesh,
                                           variable_id, integration_order,
                                           _shapefunction_order, parameters);
diff --git a/ProcessLib/RichardsComponentTransport/CreateRichardsComponentTransportProcess.cpp b/ProcessLib/RichardsComponentTransport/CreateRichardsComponentTransportProcess.cpp
index be71fead25d94f2a144e1a9295519963b984ade8..719f557ea8654ad523ce553958140a5e3c020833 100644
--- a/ProcessLib/RichardsComponentTransport/CreateRichardsComponentTransportProcess.cpp
+++ b/ProcessLib/RichardsComponentTransport/CreateRichardsComponentTransportProcess.cpp
@@ -86,7 +86,7 @@ std::unique_ptr<Process> createRichardsComponentTransportProcess(
         MaterialLib::Fluid::createFluidProperties(fluid_config);
 
     // Parameter for the density of the fluid.
-    auto& fluid_reference_density = ParameterLib::findParameter<double>(
+    auto const& fluid_reference_density = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__RichardsComponentTransport__fluid_reference_density}
         "fluid_reference_density", parameters, 1, &mesh);
diff --git a/ProcessLib/SmallDeformation/CreateSmallDeformationProcess.cpp b/ProcessLib/SmallDeformation/CreateSmallDeformationProcess.cpp
index 43d5bfcbd1c0fdad63cb66241c19e836f324dde4..c8fb2d2d88eefeb008a031c8ed45e53072b8b939 100644
--- a/ProcessLib/SmallDeformation/CreateSmallDeformationProcess.cpp
+++ b/ProcessLib/SmallDeformation/CreateSmallDeformationProcess.cpp
@@ -72,7 +72,7 @@ std::unique_ptr<Process> createSmallDeformationProcess(
             parameters, local_coordinate_system, config);
 
     // Solid density
-    auto& solid_density = ParameterLib::findParameter<double>(
+    auto const& solid_density = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__SMALL_DEFORMATION__solid_density}
         "solid_density", parameters, 1, &mesh);
diff --git a/ProcessLib/SmallDeformationNonlocal/CreateSmallDeformationNonlocalProcess.cpp b/ProcessLib/SmallDeformationNonlocal/CreateSmallDeformationNonlocalProcess.cpp
index b37a6a43085d2424ace61deb7a985fba193b9ac7..e80230eb01deca5493f3784be9047c05d4fae213 100644
--- a/ProcessLib/SmallDeformationNonlocal/CreateSmallDeformationNonlocalProcess.cpp
+++ b/ProcessLib/SmallDeformationNonlocal/CreateSmallDeformationNonlocalProcess.cpp
@@ -72,7 +72,7 @@ std::unique_ptr<Process> createSmallDeformationNonlocalProcess(
             parameters, local_coordinate_system, config);
 
     // Solid density
-    auto& solid_density = ParameterLib::findParameter<double>(
+    auto const& solid_density = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__SMALL_DEFORMATION_NONLOCAL__solid_density}
         "solid_density", parameters, 1, &mesh);
diff --git a/ProcessLib/ThermalTwoPhaseFlowWithPP/CreateThermalTwoPhaseFlowWithPPProcess.cpp b/ProcessLib/ThermalTwoPhaseFlowWithPP/CreateThermalTwoPhaseFlowWithPPProcess.cpp
index 441d6b92874d7d447ba2ab58ede93c26830621d2..8ad8fca48f736490f024131ea11c3933a590e187 100644
--- a/ProcessLib/ThermalTwoPhaseFlowWithPP/CreateThermalTwoPhaseFlowWithPPProcess.cpp
+++ b/ProcessLib/ThermalTwoPhaseFlowWithPP/CreateThermalTwoPhaseFlowWithPPProcess.cpp
@@ -74,25 +74,25 @@ std::unique_ptr<Process> createThermalTwoPhaseFlowWithPPProcess(
     //! \ogs_file_param{prj__processes__process__TWOPHASE_FLOW_THERMAL__mass_lumping}
     auto mass_lumping = config.getConfigParameter<bool>("mass_lumping");
     // diffusion coeff
-    auto& diff_coeff_b = ParameterLib::findParameter<double>(
+    auto const& diff_coeff_b = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__TWOPHASE_FLOW_THERMAL__diffusion_coeff_component_b}
         "diffusion_coeff_component_b", parameters, 1, &mesh);
-    auto& diff_coeff_a = ParameterLib::findParameter<double>(
+    auto const& diff_coeff_a = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__TWOPHASE_FLOW_THERMAL__diffusion_coeff_component_a}
         "diffusion_coeff_component_a", parameters, 1, &mesh);
 
     // Parameter for the density of the solid.
 
-    auto& density_solid = ParameterLib::findParameter<double>(
+    auto const& density_solid = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__TWOPHASE_FLOW_THERMAL__density_solid}
         "density_solid", parameters, 1, &mesh);
     DBUG("Use '{:s}' as density_solid parameter.", density_solid.name);
 
     // Parameter for the latent heat of evaporation.
-    auto& latent_heat_evaporation = ParameterLib::findParameter<double>(
+    auto const& latent_heat_evaporation = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__TWOPHASE_FLOW_THERMAL__latent_heat_evaporation}
         "latent_heat_evaporation", parameters, 1, &mesh);
diff --git a/ProcessLib/ThermalTwoPhaseFlowWithPP/ThermalTwoPhaseFlowWithPPLocalAssembler.h b/ProcessLib/ThermalTwoPhaseFlowWithPP/ThermalTwoPhaseFlowWithPPLocalAssembler.h
index dd17d244375c819c0dde7058b4921711dc58465f..25e058e3b2d6588049fcd7c0a9a80a6dacdff1b9 100644
--- a/ProcessLib/ThermalTwoPhaseFlowWithPP/ThermalTwoPhaseFlowWithPPLocalAssembler.h
+++ b/ProcessLib/ThermalTwoPhaseFlowWithPP/ThermalTwoPhaseFlowWithPPLocalAssembler.h
@@ -33,7 +33,7 @@ struct IntegrationPointData final
 {
     explicit IntegrationPointData(
         NodalRowVectorType const& N_, GlobalDimNodalMatrixType const& dNdx_,
-        ThermalTwoPhaseFlowWithPPMaterialProperties& material_property_,
+        ThermalTwoPhaseFlowWithPPMaterialProperties const& material_property_,
         double const& integration_weight_, NodalMatrixType const mass_operator_,
         NodalMatrixType const diffusion_operator_)
         : N(N_),
diff --git a/ProcessLib/ThermoHydroMechanics/CreateThermoHydroMechanicsProcess.cpp b/ProcessLib/ThermoHydroMechanics/CreateThermoHydroMechanicsProcess.cpp
index 125f109bd32587137bf6a05e4d97438f12119c7d..0cf615647a298bf123c99d34db70c29252026b4d 100644
--- a/ProcessLib/ThermoHydroMechanics/CreateThermoHydroMechanicsProcess.cpp
+++ b/ProcessLib/ThermoHydroMechanics/CreateThermoHydroMechanicsProcess.cpp
@@ -129,7 +129,7 @@ std::unique_ptr<Process> createThermoHydroMechanicsProcess(
             parameters, local_coordinate_system, config);
 
     // reference temperature
-    auto& reference_temperature = ParameterLib::findParameter<double>(
+    auto const& reference_temperature = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_HYDRO_MECHANICS__reference_temperature}
         "reference_temperature", parameters, 1, &mesh);
diff --git a/ProcessLib/ThermoMechanicalPhaseField/CreateThermoMechanicalPhaseFieldProcess.cpp b/ProcessLib/ThermoMechanicalPhaseField/CreateThermoMechanicalPhaseFieldProcess.cpp
index 9abdc346699a759dc7d1d42d2df8a8be9f78f022..fb8fd5db6c7ffa0dc71ad112626b0c9554646995 100644
--- a/ProcessLib/ThermoMechanicalPhaseField/CreateThermoMechanicalPhaseFieldProcess.cpp
+++ b/ProcessLib/ThermoMechanicalPhaseField/CreateThermoMechanicalPhaseFieldProcess.cpp
@@ -128,42 +128,42 @@ std::unique_ptr<Process> createThermoMechanicalPhaseFieldProcess(
         config.getConfigSubtree("thermal_parameters");
 
     // Residual stiffness
-    auto& residual_stiffness = ParameterLib::findParameter<double>(
+    auto const& residual_stiffness = ParameterLib::findParameter<double>(
         phasefield_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICAL_PHASE_FIELD__phasefield_parameters__residual_stiffness}
         "residual_stiffness", parameters, 1, &mesh);
     DBUG("Use '{:s}' as residual stiffness.", residual_stiffness.name);
 
     // Crack resistance
-    auto& crack_resistance = ParameterLib::findParameter<double>(
+    auto const& crack_resistance = ParameterLib::findParameter<double>(
         phasefield_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICAL_PHASE_FIELD__phasefield_parameters__crack_resistance}
         "crack_resistance", parameters, 1, &mesh);
     DBUG("Use '{:s}' as crack resistance.", crack_resistance.name);
 
     // Crack length scale
-    auto& crack_length_scale = ParameterLib::findParameter<double>(
+    auto const& crack_length_scale = ParameterLib::findParameter<double>(
         phasefield_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICAL_PHASE_FIELD__phasefield_parameters__crack_length_scale}
         "crack_length_scale", parameters, 1, &mesh);
     DBUG("Use '{:s}' as crack length scale.", crack_length_scale.name);
 
     // Kinetic coefficient
-    auto& kinetic_coefficient = ParameterLib::findParameter<double>(
+    auto const& kinetic_coefficient = ParameterLib::findParameter<double>(
         phasefield_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICAL_PHASE_FIELD__phasefield_parameters__kinetic_coefficient}
         "kinetic_coefficient", parameters, 1, &mesh);
     DBUG("Use '{:s}' as kinetic coefficient.", kinetic_coefficient.name);
 
     // Solid density
-    auto& solid_density = ParameterLib::findParameter<double>(
+    auto const& solid_density = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICAL_PHASE_FIELD__reference_solid_density}
         "solid_density", parameters, 1, &mesh);
     DBUG("Use '{:s}' as solid density parameter.", solid_density.name);
 
     // Linear thermal expansion coefficient
-    auto& linear_thermal_expansion_coefficient = ParameterLib::findParameter<
+    auto const& linear_thermal_expansion_coefficient = ParameterLib::findParameter<
         double>(
         thermal_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICAL_PHASE_FIELD__thermal_parameters__linear_thermal_expansion_coefficient}
@@ -172,21 +172,22 @@ std::unique_ptr<Process> createThermoMechanicalPhaseFieldProcess(
          linear_thermal_expansion_coefficient.name);
 
     // Specific heat capacity
-    auto& specific_heat_capacity = ParameterLib::findParameter<double>(
+    auto const& specific_heat_capacity = ParameterLib::findParameter<double>(
         thermal_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICAL_PHASE_FIELD__thermal_parameters__specific_heat_capacity}
         "specific_heat_capacity", parameters, 1, &mesh);
     DBUG("Use '{:s}' as specific heat capacity.", specific_heat_capacity.name);
 
     // Thermal conductivity
-    auto& thermal_conductivity = ParameterLib::findParameter<double>(
+    auto const& thermal_conductivity = ParameterLib::findParameter<double>(
         thermal_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICAL_PHASE_FIELD__thermal_parameters__thermal_conductivity}
         "thermal_conductivity", parameters, 1, &mesh);
     DBUG("Use '{:s}' as thermal conductivity parameter.",
          thermal_conductivity.name);
     // Residual thermal conductivity
-    auto& residual_thermal_conductivity = ParameterLib::findParameter<double>(
+    auto const& residual_thermal_conductivity = ParameterLib::findParameter<
+        double>(
         thermal_parameters_config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICAL_PHASE_FIELD__thermal_parameters__residual_thermal_conductivity}
         "residual_thermal_conductivity", parameters, 1, &mesh);
diff --git a/ProcessLib/ThermoMechanics/CreateThermoMechanicsProcess.cpp b/ProcessLib/ThermoMechanics/CreateThermoMechanicsProcess.cpp
index 0bc065a17f074398652430adb46dd3a1e262ca7c..16844323e017c702cc35dab235855e16938f1cc3 100644
--- a/ProcessLib/ThermoMechanics/CreateThermoMechanicsProcess.cpp
+++ b/ProcessLib/ThermoMechanics/CreateThermoMechanicsProcess.cpp
@@ -119,7 +119,7 @@ std::unique_ptr<Process> createThermoMechanicsProcess(
             parameters, local_coordinate_system, config);
 
     // Reference solid density
-    auto& reference_solid_density = ParameterLib::findParameter<double>(
+    auto const& reference_solid_density = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICS__reference_solid_density}
         "reference_solid_density", parameters, 1, &mesh);
@@ -127,22 +127,22 @@ std::unique_ptr<Process> createThermoMechanicsProcess(
          reference_solid_density.name);
 
     // Linear thermal expansion coefficient
-    auto& linear_thermal_expansion_coefficient = ParameterLib::findParameter<
-        double>(
-        config,
-        //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICS__linear_thermal_expansion_coefficient}
-        "linear_thermal_expansion_coefficient", parameters, 1, &mesh);
+    auto const& linear_thermal_expansion_coefficient =
+        ParameterLib::findParameter<double>(
+            config,
+            //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICS__linear_thermal_expansion_coefficient}
+            "linear_thermal_expansion_coefficient", parameters, 1, &mesh);
     DBUG("Use '{:s}' as linear thermal expansion coefficient.",
          linear_thermal_expansion_coefficient.name);
     // Specific heat capacity
-    auto& specific_heat_capacity = ParameterLib::findParameter<double>(
+    auto const& specific_heat_capacity = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICS__specific_heat_capacity}
         "specific_heat_capacity", parameters, 1, &mesh);
     DBUG("Use '{:s}' as specific heat capacity parameter.",
          specific_heat_capacity.name);
     // Thermal conductivity // TODO To be changed as tensor input.
-    auto& thermal_conductivity = ParameterLib::findParameter<double>(
+    auto const& thermal_conductivity = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__THERMO_MECHANICS__thermal_conductivity}
         "thermal_conductivity", parameters, 1, &mesh);
diff --git a/ProcessLib/TwoPhaseFlowWithPP/CreateTwoPhaseFlowWithPPProcess.cpp b/ProcessLib/TwoPhaseFlowWithPP/CreateTwoPhaseFlowWithPPProcess.cpp
index 3e1e78e96143f0d6c05ed20d91794eb5783d3ca4..0fdf26e5abf4207fc4ff0c0fd3e5df500cc4ac98 100644
--- a/ProcessLib/TwoPhaseFlowWithPP/CreateTwoPhaseFlowWithPPProcess.cpp
+++ b/ProcessLib/TwoPhaseFlowWithPP/CreateTwoPhaseFlowWithPPProcess.cpp
@@ -71,7 +71,7 @@ std::unique_ptr<Process> createTwoPhaseFlowWithPPProcess(
     //! \ogs_file_param{prj__processes__process__TWOPHASE_FLOW_PP__mass_lumping}
     auto const mass_lumping = config.getConfigParameter<bool>("mass_lumping");
 
-    auto& temperature = ParameterLib::findParameter<double>(
+    auto const& temperature = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__TWOPHASE_FLOW_PP__temperature}
         "temperature", parameters, 1, &mesh);
diff --git a/ProcessLib/TwoPhaseFlowWithPrho/CreateTwoPhaseFlowWithPrhoProcess.cpp b/ProcessLib/TwoPhaseFlowWithPrho/CreateTwoPhaseFlowWithPrhoProcess.cpp
index 9929b5bba1a0a1f9f206ab7f8c131ae29828ee3c..d81a8219d55d8cd5f3070a2dd3234b0b405fe3d3 100644
--- a/ProcessLib/TwoPhaseFlowWithPrho/CreateTwoPhaseFlowWithPrhoProcess.cpp
+++ b/ProcessLib/TwoPhaseFlowWithPrho/CreateTwoPhaseFlowWithPrhoProcess.cpp
@@ -68,15 +68,15 @@ std::unique_ptr<Process> createTwoPhaseFlowWithPrhoProcess(
     //! \ogs_file_param{prj__processes__process__TWOPHASE_FLOW_PRHO__mass_lumping}
     auto const mass_lumping = config.getConfigParameter<bool>("mass_lumping");
     // diffusion coeff
-    auto& diff_coeff_b = ParameterLib::findParameter<double>(
+    auto const& diff_coeff_b = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__TWOPHASE_FLOW_PRHO__diffusion_coeff_component_b}
         "diffusion_coeff_component_b", parameters, 1, &mesh);
-    auto& diff_coeff_a = ParameterLib::findParameter<double>(
+    auto const& diff_coeff_a = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__TWOPHASE_FLOW_PRHO__diffusion_coeff_component_a}
         "diffusion_coeff_component_a", parameters, 1, &mesh);
-    auto& temperature = ParameterLib::findParameter<double>(
+    auto const& temperature = ParameterLib::findParameter<double>(
         config,
         //! \ogs_file_param_special{prj__processes__process__TWOPHASE_FLOW_PRHO__temperature}
         "temperature", parameters, 1, &mesh);