Laurinčikas A., Šiaučiūnas D., and Tekorė M. “Joint Universality of Periodic Zeta-Functions With Multiplicative Coefficients. II”. Nonlinear Analysis: Modelling and Control, Vol. 26, no. 3, May 2021, pp. 550-64, doi:10.15388/namc.2021.26.23934.