GRAȚIELA, Brânză. Sustainable Maritime Transportation System in European Union. Constanta Maritime University Annals, [S.l.], v. 27, n. 223, mar. 2019. ISSN 2067-0427. Available at: <http://annals.cmu-edu.eu/index.php/cmuannals/article/view/45>. Date accessed: 29 nov. 2020.