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Hansen K. W.K. Hamblin, J.D. Howard: , EXERCISES IN PHYSICAL GEOLOGY 5. ed. Minneapolis, Minn. 1980, VII, 225 s., ill., 28 cm, Instructor’s supplement IV, 68 s., ill. Paperback $ 9.95. Feffer and Simons Education Division, Sussex. gt [Internet]. 1. januar 1981 [henvist 11. august 2020];81. Tilgængelig hos: https://tidsskrift.dk/geografisktidsskrift/article/view/45239