Berezovsky, A. A., and Yu. A. Mitropolskiy. “Problems With Free Boundaries and Nonlocal Problems for Nonlinear Parabolic Equations”. Ukrains’kyi Matematychnyi Zhurnal 49, no. 1 (January 25, 1997): 84–97. Accessed May 20, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/4988.