Arlinsky, Y.M. (1987) “Positive spaces of boundary values and sectorial expansions of nonnegative symmetric operator ”, Ukrains’kyi Matematychnyi Zhurnal, 40(1), pp. 8–14. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/9046 (Accessed: 6 December 2025).