diff --git a/Applications/FileIO/GocadIO/GocadAsciiReader.cpp b/Applications/FileIO/GocadIO/GocadAsciiReader.cpp
index a2d1c1e30db6dca8e520af4f93a98f9c82d7383b..b484608fc514dcd1642ab412b931cecda5c1e5bd 100644
--- a/Applications/FileIO/GocadIO/GocadAsciiReader.cpp
+++ b/Applications/FileIO/GocadIO/GocadAsciiReader.cpp
@@ -239,7 +239,7 @@ MeshLib::Node* createNode(std::stringstream& sstr)
 bool parseNodes(std::ifstream& in,
                 std::vector<MeshLib::Node*>& nodes,
                 std::map<std::size_t, std::size_t>& node_id_map,
-                MeshLib::Properties& mesh_prop)
+                MeshLib::Properties const& mesh_prop)
 {
     NodeType t = NodeType::UNSPECIFIED;
     std::streampos pos = in.tellg();