AlievI. V. (2008) “Summability of series in the root functions of boundary-value problems of Bitsadze-Samarskii type”, Ukrains’kyi Matematychnyi Zhurnal, 60(4), pp. 443–452. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/3167 (Accessed: 23November2024).