Dakhil H. К., Yu. B. Zelinskii, and Klishchuk B. А. “On Weakly M-Convex Sets”. Reports of the National Academy of Sciences of Ukraine, no. 4 (April 28, 2017): 3–7. Accessed June 20, 2026. https://nasu-periodicals.org.ua/index.php/dp/article/view/5395.