Royen, W. V. (1964). Fundamentals of economic geography: An introduction to the study of resources (5th ed.). Prentice-Hall.
Chicago Style (17. basım) AtıfRoyen, William Van. Fundamentals of Economic Geography: An Introduction to the Study of Resources. 5th ed. Englewood Cliffs N.J.: Prentice-Hall, 1964.
MLA (9th ed.) AtıfRoyen, William Van. Fundamentals of Economic Geography: An Introduction to the Study of Resources. 5th ed. Prentice-Hall, 1964.
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