Kapustyan , O. V., O. M. Stanzhytskyi, and I. D. Fartushny. “Averaging Method in the Problem of Optimal Control for a Perturbed Parabolic Equation”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 74, no. 7, Aug. 2022, pp. 973 -79, doi:10.37863/umzh.v74i7.7016.