1. Mancur Olson, Jr. and Richard Zeckhauser, ‘An economic theory of alliances’, Review of Economics and Statistics, 48, 1966, pp. 266–79.
2. Mancur Olson, The Logic of Collective Action: Public Goods and the Theory of Groups, Harvard University Press, 1965, p. 29.
3. Important contributions to this literature include Jacques van Ypserle de Strihou, ‘Sharing the defence burden among Western allies’, Review of Economics and Statistics, 49, 4, 1967, pp. 527–36;
4. Bruce M. Russett, What Price Vigilance?, Yale University Press, 1970;
5. Mark Boyer, International Cooperation and Public Goods: Opportunities for the Western Alliance, John Hopkins University Press, 1993;