Romanyshyn, Ruslana. “Elementary Mathematics Education of Preschool Children in the Ukrainian Highlands”. Journal of Vasyl Stefanyk Precarpathian National University 1, no. 2-3 (December 22, 2014): 215–218. Accessed July 20, 2024. https://journals.pnu.edu.ua/index.php/jpnu/article/view/2199.