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Citations
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OUSTALET E. (1882). Une nouvelle espèce de zèbre,. La Nature, 10, 12–14.
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Romanes G.J. (1882). Animal Intelligence. New York: Appleton.
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Steinbrecht, G. (1886). Das Gymnasium des Pferdes (Paul Plinzner, Ed.). Paul Plinzner.
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Langhavel B,. (1887). Tigerpferde. Zool Jb, 2, 117–126.
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Menges J,. (1887). Die Wildesel des Somalilandes (Equus asinus somalicus). Zool. Garten., 28, 261–268.
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Noack T,. (1887). Beiträge zur Kenntnis der Säugetierfauna von Ost – und Central – Afrika. Zool Jb, 2, 200–201.
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Steel Jh,. (1887). Wild horses. J Bombay Nt Hist, 2, 253–269.
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Noack T,. (1893). Das Quagga. Zool. Garten., 34, 289–297.
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Tegetmeier, W. B., & Sutherland, C. L. (1895). Horses, asses, zebras, mules and mule breeding.
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