Sparks, B. W. Geomorphology - 2 ed. - London : Longman, 1972 - 530 p. : ilus. ; gráfs. - Geographies for advanced study . - Geographies for advanced study . LCCN: 57789 Subjects--Topical Terms: Geografía física. Dewey Class. No.: 551.4 / S6 1972