Vdovenko, T. and Dudkin, M.E. (2016) “On nonsymmetric rank one singular perturbations of selfadjoint operators”, Methods of Functional Analysis and Topology, 22(2), pp. 137–151. Available at: https://zen.imath.kiev.ua/index.php/mfat/article/view/632 (Accessed: 18 December 2025).