William the Conqueror - Complete indexed biographical information. Provided by Boise State University. - http://history.boisestate.edu/westciv/willconq/
Catholic Encyclopaedia - Article on William's life and government first published in 1909. - http://www.newadvent.org/cathen/15642c.htm
Britannia: William I, The Conqueror - Biographical article and links to related information, including the Battle of Hastings, and the ten laws established by William after the Norman conquest. - http://britannia.com/history/monarchs/mon22.html