PNG specification (second edition), November 2003:
<http://www.w3.org/TR/2003/REC-PNG-20031110/ PNG 1.2 specification, July 1999: http://png-mng.sourceforge.net/pub/png/spec/1.2/PNG 1.0 specification, October 1996:
RFC 2083 ftp://ds.internic.net/rfc/rfc2083.txt or (as a W3C Recommendation) at http://www.w3.org/TR/REC-png-961001Portable Network Graphics (PNG) Specification (Second Edition) Information technology - Computer graphics and image processing - Portable Network Graphics (PNG): Functional specification. ISO/IEC 15948:2003 (E) (November 10, 2003): David Duce and others.
Portable Network Graphics (PNG) Specification Version 1.2 (July 8, 1999): Glenn Randers-Pehrson and others (png-list).
Portable Network Graphics (PNG) Specification Version 1.0 (October 1, 1996): Thomas Boutell and others (png-list).
This man page is Copyright (c) 1998-2006 Glenn Randers-Pehrson. See png.h for conditions of use and distribution.
The PNG Specification (Second Edition) is Copyright (c) 2003 W3C. (MIT, ERCIM, Keio), All Rights Reserved.
The PNG-1.2 specification is copyright (c) 1999 Glenn Randers-Pehrson. See the specification for conditions of use and distribution.
The PNG-1.0 specification is copyright (c) 1996 Massachusetts Institute of Technology. See the specification for conditions of use and distribution.
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