1.
Ignat’ev AO, KonosevichВI. On the stability of invariant sets of a system of autonomous differential equations under constantly acting perturbations. Ukr. Mat. Zhurn. [Internet]. 1999Sep.25 [cited 2024May17];51(9):1287–1291. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/4725