B. BØGGILD, O. J. W. W. Spencer: The Falls of Niagara, their evolution and varying relations to the great lakes; characterics of the power, and the effects of its diversion. Canada Department of Mines, Geol. Surv. Branch, Ottawa 1907 (490 Sider -f 44 Tavler). Geografisk Tidsskrift, [S. l.], v. 19, 1908. Disponível em: https://tidsskrift.dk/geografisktidsskrift/article/view/49414. Acesso em: 28 mar. 2024.