• [Wiki] http://en.wikipedia.org/wiki/Okapia_johnstoni.
• [AnAge] http://genomics.senescence.info/species/entry.php?species=Okapia_johnstoni.
• [sandiegozoo] http://library.sandiegozoo.org/factsheets/okapi/okapi.htm.
• [nagonline] https://nagonline.net/wp-content/uploads/2016/03/40_Livingston2.pdf.
• [Kooy2010] Kooijman, S. (2010). Dynamic Energy Budget theory for metabolic organisation. Cambridge Univ. Press, Cambridge.