Mahoney, J. e Goertz, G. (2006) A tale of two cultures: Contrasting quantitative and qualitative research Mahoney, J. e Goertz, G. (2006) A tale of two cultures: Contrasting quantitative and qualitative research, vol. 14 (3), 227-249
Pennings, P., Keman, H. e Kleinnijenhuis, J. (2006) Doing Research in Political Science: An Introduction to Comparative Methods and Statistics Pennings, P., Keman, H. e Kleinnijenhuis, J. (2006) Doing Research in Political Science: An Introduction to Comparative Methods and Statistics, Londres: Sage
King, G; Keohane, R, e Verba, S. (1994) Designing Social Inquiry: Scientific Inference in Qualitative Research King, G; Keohane, R. e Verba, S. (1994) Designing Social Inquiry: Scientific Inference in Qualitative Research. Princeton: Princeton University Press.
Della Porta, D. e Keating, M. (2008) Approaches and Methodologies in Social Sciences Della Porta, D. e Keating, M. (2008) Approaches and Methodologies in Social Sciences. Cambridge: Cambridge University Press.