Kuznetsova, A. Yu., and Ye. V. Patrin. “On the Structure of $C^*$-Algebra Generated by a Family of Partial Isometries and Multipliers”. Armenian Journal of Mathematics 7, no. 1 (May 27, 2015): 50–58. Accessed April 3, 2025. https://armjmath.sci.am/index.php/ajm/article/view/110.