[http://wiki.roberttwomey.com/images/1/13/13_Ways_Blackbird.pdf 13 Ways of Looking At A Blackbird] by Thomas McEvilley.
[http://wiki.roberttwomey.com/images/b/b8/Do_Digitally_Altered_Photos_Represent_Fact_or_Fiction_-_WSJ.pdf Do Digitally Altered Photos Represent Fact or Fiction - WSJ] ([http://www.wsj.com/articles/do-digitally-altered-photos-represent-fact-or-fiction-1470940019 original link with live content])
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