Presidents
http://www.americanpresidents.org/
http://www.pbs.org/wgbh/amex/presidents/
 http://www.ipl.org/div/potus/
 http://www.presidentsusa.net/ 
http://www.whitehouse.gov/about/history/
 http://www.ipl.org/div/farq/POTUSFARQ.html