http://library.thinkquest.org/20830/Manipulating/Experimentation/GenEngineering/history.htm
http://en.wikipedia.org/wiki/Aurochs
http://en.wikipedia.org/wiki/History_of_genetic_engineering
http://historyofgeneticengineering.com/ar/genetic-engineering-in-agriculture.php
http://americanradioworks.publicradio.org/features/gmos_india/history.html
http://library.thinkquest.org/04apr/00774/en/history.html
http://www.ucsusa.org/food_and_agriculture/our-failing-food-system/genetic-engineering/