Johnson, M. B., & Johnson, T. L. (1994). Study guide to accompany: Seitz, Nelson, Harcrow, Economics of resources, agriculture, and food. New York: McGraw-Hill.
Chicago Style aipamenaJohnson, Marvin B., và Tera L. Johnson. Study Guide to Accompany: Seitz, Nelson, Harcrow, Economics of Resources, Agriculture, and Food. New York: McGraw-Hill, 1994.
MLA aipamenaJohnson, Marvin B., và Tera L. Johnson. Study Guide to Accompany: Seitz, Nelson, Harcrow, Economics of Resources, Agriculture, and Food. New York: McGraw-Hill, 1994.
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