diff --git a/ProcessLib/SmallDeformation/CreateSmallDeformationProcess.h b/ProcessLib/SmallDeformation/CreateSmallDeformationProcess.h
index 2c0afd02883be2f36aa6cde92cf571f347fcd6e2..5ee96959506dc41ba09bde4c79ba5de8c82a9bb9 100644
--- a/ProcessLib/SmallDeformation/CreateSmallDeformationProcess.h
+++ b/ProcessLib/SmallDeformation/CreateSmallDeformationProcess.h
@@ -9,7 +9,24 @@
 
 #pragma once
 
-#include "ProcessLib/Process.h"
+#include <memory>
+#include <vector>
+
+namespace BaseLib
+{
+class ConfigTree;
+}
+namespace MeshLib
+{
+class Mesh;
+}
+namespace ProcessLib
+{
+class AbstractJacobianAssembler;
+struct ParameterBase;
+class Process;
+class ProcessVariable;
+}
 
 namespace ProcessLib
 {
diff --git a/ProcessLib/SmallDeformation/SmallDeformationProcessData.h b/ProcessLib/SmallDeformation/SmallDeformationProcessData.h
index 72e9dbae7552a457ef8ca163b56b27e11a2ff7cb..3aca5d5630dc0f8263ec91a3bdf41523a00dd6c2 100644
--- a/ProcessLib/SmallDeformation/SmallDeformationProcessData.h
+++ b/ProcessLib/SmallDeformation/SmallDeformationProcessData.h
@@ -9,6 +9,14 @@
 
 #pragma once
 
+namespace MaterialLib
+{
+namespace Solids
+{
+template <int DisplacementDim>
+struct MechanicsBase;
+}
+}
 namespace ProcessLib
 {
 namespace SmallDeformation