Hallet, J.P. 1977.Animal kitabu.In:Anonymous 1977.Wild, wild world of animals: Elephants & other land giants (based on the television series).New York, Time-Life Films.pp. 86-88.
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Hallet, J.P. 1969.Animal kitabu.New York, Fawcett Crest Book.pp. 1-256.