Oleskovicz, N. et al. 2006. Preemptive effects of epidural s (+) - ketamine or ketamine in the horse’s postincisional pain. Brazilian Journal of Veterinary Research and Animal Science. 43, 1 (Feb. 2006), 24–32. DOI:https://doi.org/10.11606/issn.1678-4456.bjvras.2006.26514.