Краснодембський, А. М. (2019) “PERIODICITY OF DECISIONS OF SYSTEM OF TWO NONLINEAR DIFFERENTIAL EQUALIZATIONS OF THE THIRD ORDER”, PRECARPATHIAN BULLETIN OF THE SHEVCHENKO SCIENTIFIC SOCIETY. Number, (1(13), pp. 39–42. Available at: https://pvntsh.nung.edu.ua/index.php/number/article/view/260 (Accessed: 5 December 2025).