Sukhorolsky , M.A., Veselovska , O.V. and Dostoina , V.V. 2021. Systems of complex variable polynomials related to classical systems of orthogonal polynomials. Ukrains’kyi Matematychnyi Zhurnal. 73, 11 (Nov. 2021), 1516 - 1531. DOI:https://doi.org/10.37863/umzh.v73i11.6699.