1. Feist, J. D., and McCullough, D. R., 1976, Behavior patterns and communication in feral horses, Z. Tierpsychol., 41: 337.
2. Klingel, H., 1974, A comparison of the social behaviour of the Equidae, in: “The Behavior of Ungulates and its Relation to Management,” V. Geist, and F. Walther, eds., IUCN Publ. 24, Morges, Switzerland.
3. Klingel, H., 1977, Observations on social organization and behaviour of African and Asiatic wild asses (Equus
africanus and E. hemionus), Z. Tierpsychol., 44: 323.
4. Mohr, E., 1971, “The Asiatic Wild Horse,” J. A. Allen, London.
5. Trumler, E., 1958, Beobachtungen an den Böhm-Zebras des Georg von Opel- Freigeheges für Tierforschung. I. Das Paarungsverhalten, Säugetierk. Mitt., 6: 1.