FRICKE, W. Bericht über Agrargeographische Untersuchungen in der Gombe Division, Bauchi Province, Nord-Nigeria. ERDKUNDE, [S. l.], v. 19, n. 3, p. 233–248, 1965. DOI: 10.3112/erdkunde.1965.03.05. Disponível em: https://journals-test.ulb.uni-bonn.de/index.php/erdkunde/article/view/1473. Acesso em: 7 oct. 2024.