S. Hassi, M. M. Malamud, and V. I. Mogilevskii, “Generalized resolvents and boundary triplets for dual pairs of linear relations”, MFAT, vol. 11, no. 2, pp. 170–187, Jun. 2005, Accessed: Dec. 16, 2025. [Online]. Available: https://zen.imath.kiev.ua/index.php/mfat/article/view/275