BOROGOVAC, Muhamed. IN MEMORIAM - Prof. Heinz Langer. Sarajevo Journal of Mathematics, [S. l.], v. 20, n. 2, p. 193–195, 2025. DOI: 10.5644/SJM.20.02.01. Disponível em: https://sjm.anubih.ba/index.php/sjm/article/view/512. Acesso em: 5 nov. 2025.