Kuznetsova, Victoriya. “MODEL REPRESENTATIONS OF THE LIE ALGEBRA $[A_2, A_1] = iA_1$ OF LINEAR NON-SELFADJOINT OPERATORS”. Ann. Sofia Univ. Fac. Math. and Inf. 100 (December 12, 2011): 93–112. Accessed January 15, 2025. https://admin.uni-sofia.bg/index.php/fmi/article/view/248.