Porter, V. & Mason, I. L. (2002). Mason’s World Dictionary of livestock breeds, types and varieties (5th ed.). Wallingford, Oxfordshire, UK: CABI.
Rege, J. E. O. (1999). The state of African Cattle Genetic Resources I. Classification Framework and identification of threatened and extinct breeds. Animal Genetic Resources Information, 25, 1–25. https://doi.org/10.1017/s1014233900003448
Sluyter, A. (2014). Black Ranching Frontiers: African Cattle Herders of the Atlantic World, 1500-1900. New Haven, CT: Yale University Press.