1. Reproductive and social behaviour of the northern elephant seal;Bartholomew;Univ. Calif. Publ. Zool,1952
2. Vocalization and social behaviour of the northern elephant seal;Bartholomew;Bull. Ecol. Soc. Amer,1959
3. An ecological and functional classification of animal sounds;Collias,1960
4. The spectrographic analysis of sound signals of the domestic fowl;Collias;Behaviour,1953
5. Specific distinctiveness in the communication signals of birds;Marler;Behaviour,1957