MitropolskyY. A., SheveloV. N., LuchkaA. Y., and KurpelN. S. 1966. “Yury Dmitrievich Sokolov (on His Seventieth Birthday)”. Ukrains’kyi Matematychnyi Zhurnal 18 (4), 94-101. https://umj.imath.kiev.ua/index.php/umj/article/view/8316.