diff --git a/Src/Inputs/InputSource.cpp b/Src/Inputs/InputSource.cpp
index 94f004b..79aadc9 100644
--- a/Src/Inputs/InputSource.cpp
+++ b/Src/Inputs/InputSource.cpp
@@ -31,6 +31,7 @@
 
 #include "Supermodel.h"
 #include "Input.h"
+#include "InputSystem.h"
 
 #include <vector>
 using namespace std;
diff --git a/Src/Inputs/InputSource.h b/Src/Inputs/InputSource.h
index de473c4..675d0d0 100644
--- a/Src/Inputs/InputSource.h
+++ b/Src/Inputs/InputSource.h
@@ -30,7 +30,6 @@
 
 #include <string>
 
-class CInputSystem;
 struct ForceFeedbackCmd;
 
 /*