Aminov YA. On 2-dimensional surfaces in 3-dimensional and 4-dimensional Euclidean spaces. Results and unsolved problems. Ukr. Mat. Zhurn. [Internet]. 2019 Jan. 25 [cited 2025 Apr. 13];71(1):3-36. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/1416