MORKŪNAS, Z. On the Occasion of the Anniversary. Problemos, [S. l.], v. 3, p. 106–107, 1969. DOI: 10.15388/Problemos.1969.3.5755. Disponível em: https://www.zurnalai.vu.lt/problemos/article/view/5755. Acesso em: 15 nov. 2025.