Loundsbury, J. F. (1986). Introduction to geographic field methods and techniques GA151 (3rd ed.). Merrill Publishing.
Chicago-referens (17:e uppl.)Loundsbury, John F. Introduction to Geographic Field Methods and Techniques GA151. 3rd ed. Columbia, Ohio: Merrill Publishing, 1986.
MLA-referens (9:e uppl.)Loundsbury, John F. Introduction to Geographic Field Methods and Techniques GA151. 3rd ed. Merrill Publishing, 1986.
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