Singh, S., Wulf, D., Hussain, R., Bankole, A., & Sedgh, G. (2012). Abortion Worldwide: A decade of uneven progress. GUTTMACHER INSTITUTE.
Chicago-viite (17. p.)Singh, Susheela, Deirdre Wulf, Rubina Hussain, Akinrinola Bankole, ja Gilda Sedgh. Abortion Worldwide: A Decade of Uneven Progress. GUTTMACHER INSTITUTE, 2012.
MLA-viite (8. p.)Singh, Susheela, et al. Abortion Worldwide: A Decade of Uneven Progress. GUTTMACHER INSTITUTE, 2012.
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