Antonelli, Alexandre Coutinho, et al. “Ammonia Poisoning in Cattle Fed Extruded or Prilled Urea: Alterations in Some Chemistry Components”. Brazilian Journal of Veterinary Research and Animal Science, vol. 46, no. 1, Feb. 2009, pp. 69-76, https://doi.org/10.11606/issn.1678-4456.bjvras.2009.26752.