Leyan, V., F. Wittwer, P. A. Contreras, and J. Kruze. 2004. “Serum and Colostrum Immunoglobulin Concentrations from Selenium Deficient Cows and in the Blood of Their Calves”. Archivos De Medicina Veterinaria 36 (2):155-62. https://doi.org/10.4067/S0301-732X2004000200006.