B. G. de Souza, C. C. P. da Veiga, G. F. de Oliveira, A. M. R. Ferreira, and F. Q. de Almeida, “Evaluation of a training program for eventing horses: effects on heart rate and lactate threshold”, Braz. J. Vet. Med., vol. 35, no. 4, pp. 385–391, Dec. 2013.