Pharr, Susan J., Robert D. Putnam, and Russel J. Dalton. "A Quarter Century of Declining Confidence: Trouble in Advanced   Democracies?" Journal of Democracy 11 (2000): 5-25.

Putnam, Robert D.. "Diplomacy and Domestic Politics: The Logic of Two-level Games." International Organization 42, no. 3 (1988): 427-60.