diff --git a/ProcessLib/HT/CreateHTProcess.cpp b/ProcessLib/HT/CreateHTProcess.cpp
index 05ea1c3cf0d9a7ad75c30a86245104dc23d18655..f5124f3ea67c0cce8b9aae2229706fcc1a850a28 100644
--- a/ProcessLib/HT/CreateHTProcess.cpp
+++ b/ProcessLib/HT/CreateHTProcess.cpp
@@ -50,8 +50,8 @@ std::unique_ptr<Process> createHTProcess(
          "pressure"});
 
     MaterialLib::PorousMedium::PorousMediaProperties porous_media_properties{
-        MaterialLib::PorousMedium::createPorousMediaProperties(mesh, config,
-                                                               parameters)};
+        MaterialLib::PorousMedium::createPorousMediaProperties(
+            mesh, config, parameters)};
 
     //! \ogs_file_param{prj__processes__process__HT__fluid}
     auto const& fluid_config = config.getConfigSubtree("fluid");
diff --git a/ProcessLib/HT/HTFEM.h b/ProcessLib/HT/HTFEM.h
index 21d082bb794572a2416ccfd6f2166c7f7c6b8548..561dd39acef7ed6763072c69662189d96621cb3f 100644
--- a/ProcessLib/HT/HTFEM.h
+++ b/ProcessLib/HT/HTFEM.h
@@ -12,7 +12,6 @@
 #include <Eigen/Dense>
 #include <vector>
 
-
 #include "HTMaterialProperties.h"
 
 #include "NumLib/DOF/DOFTableUtil.h"
diff --git a/ProcessLib/HT/HTProcess.cpp b/ProcessLib/HT/HTProcess.cpp
index 5c634c84e829eefd21e5771460ee0c2ad5470247..3d993042da7effe60df5cf170a569d51148fab14 100644
--- a/ProcessLib/HT/HTProcess.cpp
+++ b/ProcessLib/HT/HTProcess.cpp
@@ -13,6 +13,8 @@
 
 #include "ProcessLib/Utils/CreateLocalAssemblers.h"
 
+#include "HTMaterialProperties.h"
+
 #include "MonolithicHTFEM.h"
 #include "StaggeredHTFEM.h"
 
diff --git a/ProcessLib/HT/HTProcess.h b/ProcessLib/HT/HTProcess.h
index c1d2bb5da0d959988647eeb006288be230ea51dd..ce773e5807b0dfc8a189d56c6e9746152ee0e419 100644
--- a/ProcessLib/HT/HTProcess.h
+++ b/ProcessLib/HT/HTProcess.h
@@ -9,7 +9,6 @@
 
 #pragma once
 
-#include "HTMaterialProperties.h"
 #include "NumLib/Extrapolation/LocalLinearLeastSquaresExtrapolator.h"
 #include "ProcessLib/Process.h"
 
@@ -18,6 +17,7 @@ namespace ProcessLib
 namespace HT
 {
 class HTLocalAssemblerInterface;
+struct HTMaterialProperties;
 
 /**
  * # HT process
diff --git a/ProcessLib/HT/MonolithicHTFEM.h b/ProcessLib/HT/MonolithicHTFEM.h
index 6efaba1a7e1032912c0890b222fe2a6792600a2b..04d167672d2b5d0f0fcf75b647c5bb27ee9fdeef 100644
--- a/ProcessLib/HT/MonolithicHTFEM.h
+++ b/ProcessLib/HT/MonolithicHTFEM.h
@@ -14,7 +14,7 @@
 #include <Eigen/Dense>
 #include <vector>
 
-#include "HTProcessData.h"
+#include "HTMaterialProperties.h"
 #include "NumLib/DOF/DOFTableUtil.h"
 #include "NumLib/Extrapolation/ExtrapolatableElement.h"
 #include "NumLib/Fem/FiniteElement/TemplateIsoparametric.h"