Alan Guttmacher Institute. (1981). Teenage pregnancy: The problem that hasn?t gone away. Alan Guttmacher Institute.
Chicago-viite (17. p.)Alan Guttmacher Institute. Teenage Pregnancy: The Problem That Hasn?t Gone Away. New York: Alan Guttmacher Institute, 1981.
MLA-viite (9. p.)Alan Guttmacher Institute. Teenage Pregnancy: The Problem That Hasn?t Gone Away. Alan Guttmacher Institute, 1981.
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