diff --git a/src/cw/mavl_create_conststr.c b/src/cw/mavl_create_conststr.c
index 987465aa..7fcba3a4 100644
--- a/src/cw/mavl_create_conststr.c
+++ b/src/cw/mavl_create_conststr.c
@@ -1,3 +1,26 @@
+/*
+    This file is part of actube.
+
+    actube is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libcapwap is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with Foobar.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+/**
+ * @file
+ * @brief Implementation of mavl_create_conststr
+ */
+
 
 #include "mavl.h"
 
@@ -6,6 +29,14 @@ static int cmp(const void *v1,const void*v2)
 	return strcmp( (char*)v1,(char*)v2);
 }
 
+/**
+ * Create a mavl object which holds pointers to strings.
+ * These strings have to be constant. So there is no 
+ * free method called, when the mavl object is destroyed
+ * @return The created mavl object or NULL if an error 
+ * has occured.
+ */
+
 mavl_conststr_t mavl_create_conststr() 
 {
 	return mavl_create(cmp,NULL);