Gray, James, Sir, 1891-1975.
How animals move
Cambridge University Press, 2013
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Benyus, Janine M. author
The Secret language of animals : a guide to remarkable behavior
Black Dog & Leventhal Publishers, 2014
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Carruthers, Peter
The animals issue: moral theory in practice
Cambridge University Press, 1992
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Kendeigh, S. Charles
Ecology with special preference to animals and man
Prentice-Hall, 1975
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The encyclopedia of domestic animals
edited by Peter Messent and Donald Broom
Grolier International, 1993
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