diff --git a/FileIO/TetGenInterface.cpp b/FileIO/TetGenInterface.cpp
index 32efd553b55a8e1884a42526a3cefd51f5c1f745..ad009c5e93b724430ddd8995a4ba680cfb4eb6e2 100644
--- a/FileIO/TetGenInterface.cpp
+++ b/FileIO/TetGenInterface.cpp
@@ -112,7 +112,7 @@ std::size_t TetGenInterface::getNFacets(std::ifstream &input) const
 
 bool TetGenInterface::parseFacets(std::ifstream &input,
                                   std::vector<GeoLib::Surface*> &surfaces,
-                                  std::vector<GeoLib::Point*> &points)
+                                  std::vector<GeoLib::Point*> &points) const
 {
 	const std::size_t nFacets (this->getNFacets(input));
 	std::size_t nMultPolys (0);
@@ -361,7 +361,7 @@ bool TetGenInterface::parseNodes(std::ifstream &ins,
 
 bool TetGenInterface::readElementsFromStream(std::ifstream &ins,
                                              std::vector<MeshLib::Element*> &elements,
-                                             const std::vector<MeshLib::Node*> &nodes)
+                                             const std::vector<MeshLib::Node*> &nodes) const
 {
 	std::string line;
 	getline (ins, line);
diff --git a/FileIO/TetGenInterface.h b/FileIO/TetGenInterface.h
index 41f03471514dc9b34db38595054e5bc14bf72a14..72ca2c04618a2dabfe7e2134e9633a2879395eea 100644
--- a/FileIO/TetGenInterface.h
+++ b/FileIO/TetGenInterface.h
@@ -84,7 +84,7 @@ private:
 	 */
 	bool parseFacets(std::ifstream &input,
 	                 std::vector<GeoLib::Surface*> &surfaces,
-	                 std::vector<GeoLib::Point*> &points);
+	                 std::vector<GeoLib::Point*> &points) const;
 
 	/**
 	 * Method reads the nodes from stream and stores them in a node vector.