GRABOWSKY, A. Geopolitik und Geographie. ERDKUNDE, [S. l.], v. 16, n. 3, p. 216–219, 1962. DOI: 10.3112/erdkunde.1962.03.05. Disponível em: https://journals-test.ulb.uni-bonn.de/index.php/erdkunde/article/view/1390. Acesso em: 8 oct. 2024.