Petunin , Yu. I., and V. I. Savkin. “Convergence, Brought to Life by Analytical Functionals, and Isomorphism of Analytical-Function Algebras”. Ukrains’kyi Matematychnyi Zhurnal, vol. 40, no. 6, Nov. 1988, pp. 799-03, https://umj.imath.kiev.ua/index.php/umj/article/view/9296.