Maluf, D. Z., Pires, A. V., Susin, I., Moreira, R. J. de C., Madureira, E. H., Binelli, M., Gonçalves, J. R., Lima, L. G. de, Mendes, C. Q. and Biehl, M. V. (2010) “Evaluation of used progestagen implants on pregnancy rate in beef cows”, Brazilian Journal of Veterinary Research and Animal Science, 47(1), pp. 38-46. doi: 10.11606/issn.1678-4456.bjvras.2010.26847.