ROYEN, W. V., & BENGTSON, N. A. (1964). Fundamentals of economic geography: An introduction tothe study of resources. Prentice-Hall.
Chicago-viite (17. p.)ROYEN, William Van, ja Nels A. BENGTSON. Fundamentals of Economic Geography: An Introduction Tothe Study of Resources. Englewood Cliffs: Prentice-Hall, 1964.
MLA-viite (9. p.)ROYEN, William Van, ja Nels A. BENGTSON. Fundamentals of Economic Geography: An Introduction Tothe Study of Resources. Prentice-Hall, 1964.
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