PFEFFER, K.-H. Kalkkrusten und Kegelkarst. ERDKUNDE, [S. l.], v. 23, n. 3, p. 230–236, 1969. DOI: 10.3112/erdkunde.1969.03.08. Disponível em: https://journals-test.ulb.uni-bonn.de/index.php/erdkunde/article/view/1590. Acesso em: 7 oct. 2024.