1. Alexander Wendt, “On Constitution and Causation in International Relations,” Review of International Studies 24 (1998): 101–118.
2. Strom, “A Behavioral Theory of Competitive Political Parties”; Panebianco, Political Parties, 14; Howard E. Aldrich, “Organizational Boundaries and Interorganizational Conflict,” in Organizational Systems, ed. Frank Baker (Homewood: Irving-Dorsey, 1973), 379–393.
3. Edmond Costantini and Joel King, “The Motives of Political Party Activists: A Factor-Analytic Exploration,” Political Behavior 6 (1984): 81.
4. See examples such as Richard C. Hoftstetter, “Organizational Activists: The Bases of Participation in Amateur and Professional Groups,” American Politics Quarterly 1 (1973): 244–276
5. and Thomas H. Roback, “Motivation for Activism Among Republican National. Convention Delegates: Continuity and Change, 1972–1976,” Journal of Politics 42 (1980): 181–201.