Introduction The Challenge of the Threshold : Border Closures and Migration Movements in Africa /Streiff-Fénart, Jocelyne (ed.) Segatti, A. Lexington Books /Streiff-Fénart, Jocelyne (ed.) Segatti, A. (ed.) 2011 text https://www.documentation.ird.fr/hor/PAR00009727 PAR00009727 Streiff-Fénart Jocelyne (ed.), Segatti A., . Introduction. In : Streiff-Fénart Jocelyne (ed.), Segatti A. (ed.), . The Challenge of the Threshold : Border Closures and Migration Movements in Africa Lexington Books, 2011, EN