Стенцель, Й. І., О. І. Проказа, and К. А. Літвінов. “The Method of a Three-Dimensional Integral Functional in a Study of Multiparameter Objects of Control and Management”. Eastern-European Journal of Enterprise Technologies, vol. 1, no. 2(73), Feb. 2015, pp. 36-43, doi:10.15587/1729-4061.2015.36653.