Альрефаи, Валид Ахмед, and Ракан Абед Алнаби Альджаафрех Мохаммад. 2015. “Developing Methods for Investigating Stable Motions in Lotka-Volterra Systems With Periodic Perturbations”. Eastern-European Journal of Enterprise Technologies 1 (4(73):58-61. https://doi.org/10.15587/1729-4061.2015.37800.