Παραπομπή σε μορφή APA (7η εκδ.)

Pennings, P., Keman, H., & Kleinnijenhuis, J. (1999). Doing research in political science: An introduction to comparative methods and statistics. Sage.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Pennings, Paul, Hans Keman, και J. Kleinnijenhuis. Doing Research in Political Science: An Introduction to Comparative Methods and Statistics. London: Sage, 1999.

Παραπομπή σε μορφή MLA (9th εκδ.)

Pennings, Paul, et al. Doing Research in Political Science: An Introduction to Comparative Methods and Statistics. Sage, 1999.