1. J.L. Allen(1976 ), "Lands of Myth, Waters of Wonder: The Place of Imagination in the History of Geographical Exploration," pp.41 -62 of Lowenthal and Bowden (1976).
2. M. Bowden(1976 ), "The Great American Desert in the American Mind: The Historiography of a Geographical Notion," pp.119 -47 of Lowenthal and Bowden (1976).