1. The Complex Vocal Repertoire of the Adult Cotton-top Tamarin (Saguinus oedipus oedipus)1)
2. : Duetting in male and female songs of the white-cheeked gibbon (Hylobates concolor leucogenys), pp 67-93 in Primate Communication. and eds. New York, Cambridge University Press, 1982.
3. Markov Sequences in Songs of American Thrushes
4. : The ecological and social significance of duetting, pp 85-124 in Acoustic Communication in Birds, Vol. 2, Song Learning and Its Consequences. eds. New York, Academic Press, 1982.