Gonçalves, Ernani Ibira, and Aramis Augusto Pinto. “Efficiency Test for Foot and Mouth Disease Vaccines. I. Reduction in C Index Variation by Increasing the Number of Guinea Pigs (Cavia Cavia)”. Brazilian Journal of Veterinary Research and Animal Science, vol. 30, no. 2, Dec. 1993, pp. 137-40, https://doi.org/10.11606/issn.1678-4456.bjvras.19932.52025.