São Francisco. (n.d.). The American Heritage® Dictionary of the English Language, Fourth Edition. Retrieved December 06, 2011, from Answers.com Web site: http://www.answers.com/topic/s-o-francisco
São Francisco. (n.d.). The Columbia Electronic Encyclopedia, Sixth Edition. Retrieved December 06, 2011, from Answers.com Web site: http://www.answers.com/topic/s-o-francisco