Mendonça Jr., Cássio Xavier de, et al. “Effects of High Supplemental Dietary Copper on Laying Performance, Egg Yolk Cholesterol and Blood Plasma Lipids”. Brazilian Journal of Veterinary Research and Animal Science, vol. 36, no. 6, Jan. 1999, pp. 327-31, https://doi.org/10.1590/S1413-95961999000600009.