1. S. N. Mergelian, “On the completeness of Systems of Analytic Functions,” UMN 8(4), 3–63 (1953).
2. M. S. Melnikov, S. O. Sinanian, “Questions of Approximation Theory of Functions of One Complex Variable,” in: Contemporary Problems of Mathematics, Itogi Nauki I Tekhniki, vol. 4, 143–245 (Nauka, Moscow, 1975).
3. J. E. Brennan, “Approximation in the Mean by Polynomials on Non-Caratheodory Domains,” Ark. Math. 15(1), 117–168 (1977).
4. D. Gayer, Lectures on Approximation Theory in the Complex Domain (Mir, Moscow, 1986).
5. J. E. Brennan, “The Cauchy Integral and Certain of its Applications,” Izv. NAN Armenii, Matematika [Journal of Contemporary Mathematical Analysis (Armenian Academy of Sciences)] 39(1), 5–48 (2004).