diff --git a/skeletons/INTEGER.h b/skeletons/INTEGER.h
index 5313b58..a2c15af 100644
--- a/skeletons/INTEGER.h
+++ b/skeletons/INTEGER.h
@@ -85,7 +85,8 @@
 /*
  * Convert the integer value into the corresponding enumeration map entry.
  */
-const asn_INTEGER_enum_map_t *INTEGER_map_value2enum(asn_INTEGER_specifics_t *specs, long value);
+const asn_INTEGER_enum_map_t *INTEGER_map_value2enum(
+    const asn_INTEGER_specifics_t *specs, long value);
 
 #ifdef __cplusplus
 }