Ribeiro, P. R., R. N. Kronka, M. C. Thomaz, M. I. Hannas, F. M. Tucci, A. J. Scandolera, and F. E. L. Budiño. “Different Levels of Betaine on Diarrhea Incidence, Performance, Carcass Characteristics and Blood Parameters of Pigs”. Brazilian Journal of Veterinary Research and Animal Science, vol. 48, no. 4, Aug. 2011, pp. 299-06, doi:10.11606/S1413-95962011000400004.