[devel] Revise references to zlib-libpng license
diff --git a/pngrtran.c b/pngrtran.c
index f1a2b6a..52d8913 100644
--- a/pngrtran.c
+++ b/pngrtran.c
@@ -7,7 +7,8 @@
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
  * This code is released under the zlib-libpng license.
- * For conditions of distribution and use, see copyright notice in png.h
+ * For conditions of distribution and use, see copyright notice, disclaimer,
+ * and license in png.h
  *
  * This file contains functions optionally called by an application
  * in order to tell libpng how to handle data when reading a PNG.