1. Berliner V. & Warbritton V. (1937). Proc. Amer. Soc. Anim. Prod., 30th Ann. Meet. p. 137.
2. Lardy H. A. & Phillips P. H. (1939). Proc. Amer. Soc. Anim. Prod., 32nd Ann. Meet. p. 219.
3. The breeding season of the sheep with particular reference to its modification by artificial means using light
4. Anderson J. (1945). The Semen of Animals and Its Use in Artificial Insemination, pp. 1–23. Imp. Bur. Anim. Breed, and Gen.
5. Phillips R. W. & McKenzie F. F. (1934). Res. Bull. Mo. Agric. Exp. Sta. no. 217.