Кофанов, Володимир Олександрович. 2021. “The Bojanov-Naidenov Problem for the Functions With Non-Symmetric Restrictions on the Oldest Derivative”. Ukrains’kyi Matematychnyi Zhurnal 71 (3): 368-81. https://umj.imath.kiev.ua/index.php/umj/article/view/254.