Štenclová, H. ., F. . Karásek, O. . Šťastní­k, L. . Zeman, E. . Mrkvicová, and L. . Pavlata. “The Effect of Reduced Zinc Levels on Performance Parameters of Broiler Chickens”. Potravinarstvo Slovak Journal of Food Sciences, vol. 10, no. 1, May 2016, pp. 272-5, doi:10.5219/580.