Chorley, R.J., Beckinsale, R.P. and Dunn, A.J. (1973) The history of the study of landforms or the development of geomorphology. Vol. 2. The life and work of William Morris Davis. London, Methuen and Co., 874 p., 165 fig. - Cailleux, André (Cahiers de géographie du Québec, 1974)