Riddle, Kenton E.; Keeling, Michale E.; Roberts, Jimmy (1973). "Birth of a Lowland Gorilla (Gorilla gorilla gorilla) at the Yerkes Regional Primate Research Center". The Journal of Zoo Animal Medicine. 4 (4): 22. doi:10.2307/20094209. JSTOR20094209.
Suarez, Susan D.; Gallup, Gordon G. (February 1981). "Self-recognition in chimpanzees and orangutans, but not gorillas". Journal of Human Evolution. 10 (2): 175–188. doi:10.1016/S0047-2484(81)80016-4.
Hoff, Michael P.; Forthman, Debra L.; Maple, Terry L. (1994). "Dyadic interactions of infant lowland gorillas in an outdoor exhibit compared to an indoor holding area". Zoo Biology. 13 (3): 245–256. doi:10.1002/zoo.1430130306. ISSN0733-3188.
Riddle, Kenton E.; Keeling, Michale E.; Roberts, Jimmy (1973). "Birth of a Lowland Gorilla (Gorilla gorilla gorilla) at the Yerkes Regional Primate Research Center". The Journal of Zoo Animal Medicine. 4 (4): 22. doi:10.2307/20094209. JSTOR20094209.
Hoff, Michael P.; Forthman, Debra L.; Maple, Terry L. (1994). "Dyadic interactions of infant lowland gorillas in an outdoor exhibit compared to an indoor holding area". Zoo Biology. 13 (3): 245–256. doi:10.1002/zoo.1430130306. ISSN0733-3188.