KHRABUSTOVSKY, V. On the Characteristic Operators and Projections and on the Solutions of Weyl Type of Dissipative and Accumulative Operator Systems.III. Separated Boundary Conditions. Журнал математичної фізики, аналізу, геометрії, Харків, Україна, v. 2, n. 4, p. 449–473, 2006. Disponível em: https://jmag.ilt.kharkiv.ua/index.php/jmag/article/view/jm02-0449e. Acesso em: 23 квіт. 2024.