Мельниченко, Г. М. “Features of the Course of Pollination of the Genus Betula L. In Ivano-Frankivsk During the Period of 2013–2015”. The Journal of V.N.Karazin Kharkiv National University. Series «Biology», Vol. 26, 1, pp. 38-44, https://periodicals.karazin.ua/biology/article/view/6255.