Terčič, Dušan, and Mojca Pestotnik. 2014. “Effect of Excess Folic Acid on Egg Production, Fertility and Hatchability in Layer Breeders”. Acta Agraria Kaposváriensis 18 (1): 122-28. https://journal.uni-mate.hu/index.php/aak/article/view/2115.