[devel] Revise references to zlib-libpng license
diff --git a/pngmem.c b/pngmem.c
index eca9a2c..14927f7 100644
--- a/pngmem.c
+++ b/pngmem.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 provides a location for all memory allocation.  Users who
  * need special memory handling are expected to supply replacement