diff --git a/MathLib/MathTools.cpp b/MathLib/MathTools.cpp
index c9999f5a26337b29dab78bb7b77477d06cdb96eb..469c3ab0c033277b4801001d51c403e2bb701f45 100644
--- a/MathLib/MathTools.cpp
+++ b/MathLib/MathTools.cpp
@@ -51,4 +51,10 @@ double getAngle (const double p0[3], const double p1[3], const double p2[3])
     return std::acos (scalarProduct<double,3> (v0,v1) / (std::sqrt(scalarProduct<double,3>(v0,v0)) * sqrt(scalarProduct<double,3>(v1,v1))));
 }
 
+double scalarTriple(Eigen::Vector3d const& u, Eigen::Vector3d const& v,
+                    Eigen::Vector3d const& w)
+{
+    return u.cross(v).dot(w);
+}
+
 }  // namespace MathLib
diff --git a/MathLib/MathTools.h b/MathLib/MathTools.h
index 361a1289c473298baaace868636b97c730add130..1dcd438834cc18ed5659847c4c73fcbe73ced38e 100644
--- a/MathLib/MathTools.h
+++ b/MathLib/MathTools.h
@@ -90,4 +90,8 @@ double calcProjPntToLineAndDists(MathLib::Point3d const& pp,
  * @return the angle between the edges
  */
 double getAngle (const double p0[3], const double p1[3], const double p2[3]);
+
+/// Calculates the scalar triple (u x v) . w
+double scalarTriple(Eigen::Vector3d const& u, Eigen::Vector3d const& v,
+                    Eigen::Vector3d const& w);
 }  // namespace MathLib
diff --git a/MathLib/Vector3.cpp b/MathLib/Vector3.cpp
deleted file mode 100644
index f9e80edb2cda9bcf4175c24b8774ee31555fead5..0000000000000000000000000000000000000000
--- a/MathLib/Vector3.cpp
+++ /dev/null
@@ -1,21 +0,0 @@
-/**
- * \file
- * \copyright
- * Copyright (c) 2012-2020, OpenGeoSys Community (http://www.opengeosys.org)
- *            Distributed under a Modified BSD License.
- *              See accompanying file LICENSE.txt or
- *              http://www.opengeosys.org/project/license
- */
-
-#include "Vector3.h"
-
-namespace MathLib
-{
-
-double scalarTriple(Eigen::Vector3d const& u, Eigen::Vector3d const& v,
-                    Eigen::Vector3d const& w)
-{
-    return u.cross(v).dot(w);
-}
-
-}  // end namespace MathLib
diff --git a/MathLib/Vector3.h b/MathLib/Vector3.h
index 51ccb328613d7e071cb776dfa63a5c197722a1ab..9b9985fa50dd5f3b6d9a2d4397c9d8b1bdeb118a 100644
--- a/MathLib/Vector3.h
+++ b/MathLib/Vector3.h
@@ -196,8 +196,4 @@ template <typename T1> TemplateVector3<T1> operator*(
 }
 
 using Vector3 = TemplateVector3<double>;
-
-/// Calculates the scalar triple (u x v) . w
-double scalarTriple(Eigen::Vector3d const& u, Eigen::Vector3d const& v,
-                    Eigen::Vector3d const& w);
 }  // namespace MathLib