Arruda, Rubens Paes de, et al. “Evaluation of Frozen Bull Semen. Quick and Slow Thermoresistance Tests: Effects on Fertility”. Brazilian Journal of Veterinary Research and Animal Science, vol. 29, no. 1, June 1992, pp. 131-7, https://doi.org/10.11606/issn.1678-4456.bjvras.1992.51962.