“Content of Chemical Elements in the Ash of Black Poplar (Populus Nigra L.) Leaves in the Territory of Northern Kazakhstan”. Eurasian Journal of Ecology 69, no. 4 (December 21, 2021): 4–12. Accessed July 17, 2026. https://bulletin-ecology.kaznu.kz/index.php/1-eco/article/view/1216.