Gorbachuk ML, Lukovsky IO, Marchenko VO, Mitropolskiy YA, Pastur LA, Samoilenko AM, Skrypnik IV, Khruslov EY. Dmytro Yakovych Petryna (on his 70 th birthday). Ukr. Mat. Zhurn. [Internet]. 2004Mar.25 [cited 2024May7];56(3):291-2. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/3754