diff --git a/src/properscalarincreasingconvexfunction.hh b/src/properscalarincreasingconvexfunction.hh
index d02ad9413bb896e59239ad0ec5babcf0be05b09f..09af713c5da1df107ce66413e224380038ec6cde 100644
--- a/src/properscalarincreasingconvexfunction.hh
+++ b/src/properscalarincreasingconvexfunction.hh
@@ -1,3 +1,5 @@
+/* -*- mode:c++; mode:semantic -*- */
+
 #ifndef PROPER_SCALAR_INCREASING_CONVEX_FUNCTION_HH
 #define PROPER_SCALAR_INCREASING_CONVEX_FUNCTION_HH