BoichukОA, Makarov VL, Feruk VA. A criterion of solvability of resonant equations and construction of their solutions. Ukr. Mat. Zhurn. [Internet]. 2019Oct.25 [cited 2024Dec.26];71(10):1321-30. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/1517