diff --git a/ProcessLib/LIE/HydroMechanics/CreateHydroMechanicsProcess.cpp b/ProcessLib/LIE/HydroMechanics/CreateHydroMechanicsProcess.cpp
index ae9aa9520a26560859162d0bdea416a37544f0c5..43ff58d72a12a14ca8fa4fa9a7cab1034bd589d5 100644
--- a/ProcessLib/LIE/HydroMechanics/CreateHydroMechanicsProcess.cpp
+++ b/ProcessLib/LIE/HydroMechanics/CreateHydroMechanicsProcess.cpp
@@ -261,6 +261,7 @@ std::unique_ptr<Process> createHydroMechanicsProcess(
          initial_fracture_effective_stress.name.c_str());
 
     // deactivation of matrix elements in flow
+    //! \ogs_file_param_special{process__HYDRO_MECHANICS_WITH_LIE__deactivate_matrix_in_flow}
     auto opt_deactivate_matrix_in_flow = config.getConfigParameterOptional<bool>("deactivate_matrix_in_flow");
     bool const deactivate_matrix_in_flow = opt_deactivate_matrix_in_flow ? opt_deactivate_matrix_in_flow.get() : false;
     if (deactivate_matrix_in_flow)