diff --git a/include/c3d/maths.h b/include/c3d/maths.h
index bfccae6..8f100a5 100644
--- a/include/c3d/maths.h
+++ b/include/c3d/maths.h
@@ -627,7 +627,7 @@ void Mtx_FromQuat(C3D_Mtx* m, C3D_FQuat q);
  * @param[in]   m Input  Matrix
  * @return      Generated Quaternion
  */
-C3D_FQuat Quat_FromMtx(C3D_Mtx* m);
+C3D_FQuat Quat_FromMtx(const C3D_Mtx* m);
 
 /**
  * @brief Identity Quaternion
diff --git a/source/maths/quat_frommtx.c b/source/maths/quat_frommtx.c
index b1981f3..64bafc5 100644
--- a/source/maths/quat_frommtx.c
+++ b/source/maths/quat_frommtx.c
@@ -1,6 +1,6 @@
 #include <c3d/maths.h>
 
-C3D_FQuat Quat_FromMtx(C3D_Mtx* m)
+C3D_FQuat Quat_FromMtx(const C3D_Mtx* m)
 {
 	//Taken from Gamasutra:
 	//http://www.gamasutra.com/view/feature/131686/rotating_objects_using_quaternions.php