Population and development review. Malden Blackwell Publishing. Available on Internet: <http://web.ebscohost.com/ehost/detail?sid=0b045cc1-8ea7-4e3b-bccf-93b3f7cc1a39%40sessionmgr104&vid=1&hid=111&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=eoh&jid=PDV> ISSN 0098-7921.