Duverger, M., Pressure groups, & Wagover, R. (1972). Party politics and pressure groups: A comparative introduction. Thomas Nelson.
Chicago-viite (17. p.)Duverger, Maurice, Pressure groups, ja Robert Wagover. Party Politics and Pressure Groups: A Comparative Introduction. London, Eng: Thomas Nelson, 1972.
MLA-viite (9. p.)Duverger, Maurice, et al. Party Politics and Pressure Groups: A Comparative Introduction. Thomas Nelson, 1972.
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