1. Sperm Production and Fertility of Dairy Bulls at High-Collection Frequencies with Varying Degrees of Sexual Preparation;Almquist;J. Dairy Sci.,1958
2. Semen Production, Fructose Content of Semen and Fertility of Dairy Bulls as Belated to Sexual Excitement;Branton;J. Dairy Sci.,1952
3. Bratton, R. W., Shipman, K., and Foote, R. H. Estimating the Number of Spermatozoa in Bovine Semen by Measuring Its Opacity with a Photelometer. Routine Laboratory Procedure No. 4, Laboratory of Animal Breeding, Dept. of Animal Husbandry, Cornell University. 1955.
4. The Relationship of Semen Production to Sexual Excitement of Dairy Bulls;Collins;J. Dairy Sci.,1951
5. De Invloed van voorbereiding voor het Dekken op de Spermaproduktie en de Bevruchtingsresultaten van K. I. Stierern;Crombach;Tijdschr. Diergeneesk,1958