BRUK, V. M. Generalized Resolvents of Symmetric Relations Generated on Semi-Axis by a Differential Expression and a Nonnegative Operator Function. Журнал математичної фізики, аналізу, геометрії, Харків, Україна, v. 2, n. 4, p. 372–387, 2006. Disponível em: https://jmag.ilt.kharkiv.ua/index.php/jmag/article/view/jm02-0372e. Acesso em: 21 лис. 2024.