Kovács, Réka Katalin, János Tossenberger, és László Babinszky. 2006. „Effect of Different Phosphorus Intakes on Phosphorus Balance and Performance of Layers During Peak Production”. Acta Agraria Kaposváriensis 10 (2), 193-98. http://journal.ke.hu/index.php/aak/article/view/1794.