Bobodzhanova, M., Kalimbetov, B., & Bekmakhanbet, G. (2021). Asymptotics solutions of a singularly perturbed integro-differential fractional order derivative equation with rapidly oscillating coefficients. Bulletin of the Karaganda University. Mathematics Series, 104(4), 56–67. https://doi.org/10.31489/2021m4/56-67