B. BØGGILD, 0. World Atlas of commercial Geology. Part I. Distribution of Mineral Production. United States Geological Survey, Washington, 1921. Geografisk Tidsskrift, [S. l.], v. 26, 1922. Disponível em: https://tidsskrift.dk/geografisktidsskrift/article/view/47193. Acesso em: 20 dec. 2024.