Calvin, C. (1991). Themes in geography: International issues. Hodder & Stoughton.
Chicago Style (17th ed.) CitationCalvin, Clarke. Themes in Geography: International Issues. London: Hodder & Stoughton, 1991.
MLA (9th ed.) CitationCalvin, Clarke. Themes in Geography: International Issues. Hodder & Stoughton, 1991.
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