Weeks, J. R. (2012). Population: An introduction to concepts and issues (Eleventh edition.). Wadsworth Cengage learning.
Chicago-viite (17. p.)Weeks, John Robert. Population: An Introduction to Concepts and Issues. Eleventh edition. Belmont, CA: Wadsworth Cengage learning, 2012.
MLA-viite (8. p.)Weeks, John Robert. Population: An Introduction to Concepts and Issues. Eleventh edition. Wadsworth Cengage learning, 2012.
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