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2. Issues and Methods in Comparative Politics, 4th Edition, Oxford and London: Routledge, 2017.
3. Human Rights and Democracy: The Precarious Triumph of Ideals, London: Bloomsbury, 2013.
4. Real Social Science: Applied Phronesis, Cambridge: Cambridge University Press, 2012.
5. Politica Comparada: Una Introduccion a Su Objeto Y Metodos De Investigacion, Alianza Editorial Sa, 2011.
6. Human Rights, Volumes I-IV, London: Sage Publications, 2009.
7. Sage Handbook of Comparative Politics, London: Sage Publications, 2009.
8. Measuring Human Rights, Oxford and London: Routledge, 2009.
9. Assessing the Quality of Democracy: A Practical Handbook, Stockholm: International IDEA, 2008.
10. Issues and Methods in Comparative Politics, 3rd Edition, Oxford and London: Routledge, 2008.
11. Studying Human Rights, Oxford and London: Routledge, 2006.
12. Protecting Human Rights: A Comparative Study, Washington, DC: Georgetown University Press, 2005.
13. Issues and Methods in Comparative Politics, 2nd Edition, Oxford and London: Routledge, 2003.
14. Governing Latin America, Cambridge: Polity Press, 2003.
15. Issues and Methods in Comparative Politics, 1st Edition, Oxford and London: Routledge, 2000.
16. Citizenship Rights and Social Movements: A Comparative and Statistical Analysis, Oxford: Oxford University Press, 1997.