1. Almada, Andre Alvares d’. Tratado Brave Dos Rios de Guine’ Do Cabo-Verde, Desde o Rio Do Sanaga’ Ate’ Aos Baixos de Sant’ Anna, 1594. Facsimile. Porto: Typ. Commercial Portuense, 1841.
2. ———. Brief Treatise on The Rivers of Guinea, Part I, 1594. Edited and translated by P. E. H. Hair. Liverpool: Department of History, University of Liverpool, 1984. http://digital.library.wisc.edu/1711.dl/AfricanStudies.Almada01.
3. Aristotle. “History of Animals.” In The Complete Works of Aristotle: The Revised Oxford Translation, edited by Jonathan Barnes, 1:774–993. Princeton, NJ: Princeton University Press, 1984.
4. ———. “On The Soul.” In Aristotle: On the Soul. Parva Naturalia. On Breath, translated by Walter Stanley Hett, rev. edition. Loeb Classical Library. Cambridge, MA: Harvard University Press, 1957.
5. ———. The Complete Works of Aristotle: The Revised Oxford Translation, One-Volume Digital Edition. Princeton, NJ: Princeton University Press, 2014.