Research visit at Stanford in Washington (Washington, DC, United States), by invitation of David D. Laitin, in January 2011 (3 weeks).

Research visit at IZA – Institute of Labor Economics (Bonn, Germany), by invitation of Klaus F. Zimmermann in August 2010 (2 weeks).

Research visit at the Department of Political Science at Stanford University (Palo Alto, United States), by invitation of David D. Laitin in January 2010 (3 weeks).

Research visit at the Department of Politics of New York University (New York, United States), by invitation of Léonard Wantchekon from February to April 2008 (3 months).