Turgumbaev, M.Zh., et al. “On Conditions for the Weighted Integrability of the Sum of the Series With Monotonic Coefficients With Respect to the Multiplicative Systems”. Bulletin of the Karaganda University. Mathematics Series, vol. 114, no. 2, June 2024, pp. 197-10, doi:10.31489/2024m2/197-210.