http://en.wikipedia.org/wiki/Ralston_Crawford
◇ Ralston Crawford on artnet
http://www.artnet.com/artists/ralston-crawford/
◇ Whitney Museum of American Art: Ralston Crawford
http://whitney.org/Collection/RalstonCrawford
◇ Ralston Crawford - Google 検索
https://www.google.co.jp/search?q=Ralston+Crawford&es_sm=91&source=lnms&tbm=isch&sa=X&ei=VhcxVNrQLcPV8gX32YCgCg&ved=0CAgQ_AUoAQ&biw=1436&bih=762&dpr=2
◇ Ralston Crawford photography - Google 検索
https://www.google.co.jp/search?q=Ralston+Crawford+photography&es_sm=91&tbm=isch&tbo=u&source=univ&sa=X&ei=gRcxVMf9MYz-8QXx5oCACg&ved=0CB4QsAQ&biw=1436&bih=762