HAGGMAN, Bertil. Geopolitics of Baltic Sea Communication- Linking the Periphenes with the Centre. Promet - Traffic&Transportation, [S. l.], v. 11, n. 2-3, p. 97–104, 2012. Disponível em: https://traffic2.fpz.hr/index.php/PROMTT/article/view/2322. Acesso em: 27 aug. 2025.