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Roth, Mark, Some women may see 100,000,000 colors, thanks to their genes, Pittsburgh Post-Gazette, 2006, [1]Arkivigite je 2006-11-08 per la retarkivo Wayback Machine
Roth, Mark, Some women may see 100,000,000 colors, thanks to their genes, Pittsburgh Post-Gazette, 2006, [1]Arkivigite je 2006-11-08 per la retarkivo Wayback Machine