1. Sorger, T., Pittman, R., and Soderwall, A.L., Biol. Reprod.28 (1983) 461.
2. Rodriguez-Martinez, H., García, R.B., Ohanian, C., and Einarsson, S., Zbl. Vet. Med. A29 (1982) 64.
3. Burden, W.H., The vertebrate ovary, in: Comparative biology and evolution, p. 615. Ed. R.E. Jones. Plenum Press, New York 1978.
4. Bahr, W.H., Kao, L., and Nalbandov, A.V., Biol. Reprod.10 (1974) 273.
5. Hodson, N., in: The testis, p. 47. Eds A.D. Johnson, W.R. Gomes and N.L. Vandemark. Academic Press, New York and London 1970.