diff --git a/Solver/dofManager.h b/Solver/dofManager.h
index a95ed987fad9035bd01ffa32a49e3addaecb16f4..44cb399f2be1e773fb13c8efe2ad6786ff5295a3 100644
--- a/Solver/dofManager.h
+++ b/Solver/dofManager.h
@@ -11,6 +11,7 @@
 #include <map>
 #include "MVertex.h"
 #include "linearSystem.h"
+#include "fullMatrix.h"
 
 class Dof{
  private: