diff --git a/corsika/detail/modules/sibyll/InteractionModel.inl b/corsika/detail/modules/sibyll/InteractionModel.inl
index af1a0113394eca3ca0badd951044d0f6040054ed..38acb4b3d457bef02f81270761f7fc82716d5821 100644
--- a/corsika/detail/modules/sibyll/InteractionModel.inl
+++ b/corsika/detail/modules/sibyll/InteractionModel.inl
@@ -9,9 +9,9 @@
 #pragma once
 
 #include <corsika/framework/geometry/Point.hpp>
-#include <corsika/framework/geometry/FourVector.hpp>
 
 #include <corsika/modules/sibyll/ParticleConversion.hpp>
+#include <corsika/framework/utility/COMBoost.hpp>
 #include <corsika/modules/sibyll/SibStack.hpp>
 
 #include <sibyll2.3d.hpp>
diff --git a/corsika/detail/modules/sibyll/NuclearInteractionModel.inl b/corsika/detail/modules/sibyll/NuclearInteractionModel.inl
index 906cfa8b63074fd9f5897de4954877f89e92450d..e9ad447f33e0d25bd4d14fa735ed630d083662d9 100644
--- a/corsika/detail/modules/sibyll/NuclearInteractionModel.inl
+++ b/corsika/detail/modules/sibyll/NuclearInteractionModel.inl
@@ -11,7 +11,6 @@
 #include <corsika/media/Environment.hpp>
 #include <corsika/media/NuclearComposition.hpp>
 
-#include <corsika/framework/geometry/FourVector.hpp>
 #include <corsika/framework/core/PhysicalUnits.hpp>
 #include <corsika/framework/utility/COMBoost.hpp>
 #include <corsika/framework/core/Logging.hpp>
diff --git a/corsika/modules/sibyll/InteractionModel.hpp b/corsika/modules/sibyll/InteractionModel.hpp
index 58b9d36e1b0ade04d423957f5c13e463feb7eb7b..0f65dcab7d8b38581e141807d5eff1a234f8818d 100644
--- a/corsika/modules/sibyll/InteractionModel.hpp
+++ b/corsika/modules/sibyll/InteractionModel.hpp
@@ -11,12 +11,12 @@
 #include <corsika/framework/core/ParticleProperties.hpp>
 #include <corsika/framework/core/PhysicalUnits.hpp>
 #include <corsika/framework/random/RNGManager.hpp>
+#include <corsika/framework/geometry/FourVector.hpp>
+
 #include <tuple>
 
 namespace corsika::sibyll {
 
-  class FourMomentum; // fwd-decl
-
   /**
    * @brief sibyll::InteractionModel provides the SIBYLL proton-nucleus interaction model.
    *
diff --git a/corsika/modules/sibyll/NuclearInteractionModel.hpp b/corsika/modules/sibyll/NuclearInteractionModel.hpp
index 8072145740eb84216c14e8fce6566f40a7ad3ad5..1c4d9c7e9f085f77857ea7eff9e5c6aa6d44f940 100644
--- a/corsika/modules/sibyll/NuclearInteractionModel.hpp
+++ b/corsika/modules/sibyll/NuclearInteractionModel.hpp
@@ -11,6 +11,7 @@
 #include <corsika/framework/core/ParticleProperties.hpp>
 #include <corsika/framework/random/RNGManager.hpp>
 #include <corsika/framework/utility/COMBoost.hpp>
+#include <corsika/framework/geometry/FourVector.hpp>
 
 namespace corsika::sibyll {