Groves, C. P. (2005). "Order Primates".[1] In Wilson, D. E.; Reeder, D. M (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.).[2] Johns Hopkins University Press. p. 168. ISBN 978-0-8018-8221-0. OCLC 62265494.
Hayes, V. J.; Freedman, L.; Oxnard, C. E. (1995). »The differential expression of dental sexual dimorphism in subspecies of Colobus guereza«. International Journal of Primatology. 16 (6): 971–996. doi:10.1007/bf02696112. S2CID23753155.
Groves, C. P. (2005). "Order Primates".[1] In Wilson, D. E.; Reeder, D. M (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.).[2] Johns Hopkins University Press. p. 168. ISBN 978-0-8018-8221-0. OCLC 62265494.
Hayes, V. J.; Freedman, L.; Oxnard, C. E. (1995). »The differential expression of dental sexual dimorphism in subspecies of Colobus guereza«. International Journal of Primatology. 16 (6): 971–996. doi:10.1007/bf02696112. S2CID23753155.