Alan Guttmacher Institute. (1981). Teenage pregnancy: The problem that hasn?t gone away. Alan Guttmacher Institute.
Citazione stile Chigago Style (17a edizione)Alan Guttmacher Institute. Teenage Pregnancy: The Problem That Hasn?t Gone Away. New York: Alan Guttmacher Institute, 1981.
Citatione MLA (9a ed.)Alan Guttmacher Institute. Teenage Pregnancy: The Problem That Hasn?t Gone Away. Alan Guttmacher Institute, 1981.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.