1. Ainley, D. G., 1974, The comfort behaviour of Adelie and other penguins, Behaviour 50: 16–51.
2. Alexander, R. D., 1974, The evolution of social behavior, Annu. Rev. Ecol. Syst. 4: 325–383.
3. Alexander, R. D., and Tinkle, D. W., eds., 1981, Natural Selection and Social Behavior: Recent Research and New Theory, Chiron, New York.
4. Altmann, D., and Scheel, H. G., 1980, Beginn des Sozialverhaltens und erstes Lernen beim Milu, Elaphurus davidianus, Milu (Berl.) 5: 146–156.
5. Altmann, J., 1980, Baboon Mothers and Infants, Harvard University Press, Cambridge..