1. Adrian, E. D. The Basis of Sensation. Christophers ( Publishers ), London, 1928.
2. Altmann, S. A. A field study of the sociobiology of rhesus monkeys, Macaca mulatta. Ann. N.Y. Acad. Sci, 1962, 102, 338–435.
3. Altmann, S. A. Sociobiology of rhesus monkeys. II. Stochastics of social communication. J. Theoret. Biol 1965, 8, 490–522.
4. Altmann, S. A. The structure of primate social communication. In S. A. Altmann (ed.), Social Communication Among Primates. University of Chicago Press, Chicago, 1967.
5. Ames, P. L. The morphology of the syrinx in passerine birds. Peabody Mus. Nat. Hist. Bull., 1971, 37, 1–194.