Шагута, М. О., and Л. Д. Гулай. “BALANCE OF HUMUS OF SOILS OF VOLYN REGION AND WAYS OF HIS STABILIZING”. Visnyk of V. N. Karazin Kharkiv National University Series «Еcоlogy», Apr. 2016, pp. 86-90, https://periodicals.karazin.ua/ecology/article/view/5531.