TZVETKOVA, S. . GUIDELINES FOR IMPROVING THE ENVIRONMENTAL FRIENDLINESS AND SAFETY OF RAILWAY TRANSPORT FREIGHTS OF DANGEROUS CARGO WITHIN THE REPUBLIC OF BULGARIA. Proceedings of CBU in Economics and Business, [S. l.], v. 1, p. 141-146, 2020. DOI: 10.12955/peb.v1.31. Disponível em: https://ojs.cbuic.cz/index.php/peb/article/view/31. Acesso em: 5 nov. 2026.