my sources


http://animaldiversity.ummz.umich.edu/accounts/colobus/c._guereza -- Animal Diversity

http://www.chaffeezoo.org/zoo/animals/colobus.html -- Chaffee Zoo

http://www.selu.com/bio/PrimateGallery/PrimateWeek/Colobus/index.html -- Primate of the Week

http://www.zoo.org/ --Woodland Park Zoo
(source of the two picture links on the physical description page.

http://www.wildsanctuary.com -- Wild Sanctuary
(who generously allowed the use of their colobus vocalization file)

"Colobus Monkey." Encyclopedia Americana. Grolier Incorpporated, CO. 1987.