ФЕДАК, Іван Васильович. SOME BIJECTIVE MAPPINGS AND THEIR INVERSE FUNCTIONS. PRECARPATHIAN BULLETIN OF THE SHEVCHENKO SCIENTIFIC SOCIETY. Number, [S. l.], n. 1(21), p. 26–30, 2019. Disponível em: https://pvntsh.nung.edu.ua/index.php/number/article/view/176. Acesso em: 6 dec. 2025.