Pennings, P. (2006). Doing research in political science (2nd ed.). Sage.
Chicago-viite (17. p.)Pennings, Paul. Doing Research in Political Science. 2nd ed. London ; Thousand Oaks, Calif: Sage, 2006.
MLA-viite (9. p.)Pennings, Paul. Doing Research in Political Science. 2nd ed. Sage, 2006.
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