1. Campbell, R. and L. Sowden: 1985, Paradoxes of Rationality and Cooperation: Prisoner's Dilemma and Newcomb's Problem, Vancouver University Press, Vancouver.
2. Gardner, M.: 1973, ?Mathematical Games: Free Will Revisited, with a Mind-bending Prediction Paradox by William Newcomb?, Scientific American, July. For a report by Robert Nozick on letters to Scientific American about this column, see ?Mathematical Games? for March 1974.
3. Gibbard, A. and W. L. Harper: 1978, ?Counterfactuals and Two Kinds of Expected Utility?, in Hooker et al. (eds.), Foundations and Applications of Decision Theory 1, 125?62. (Reprinted with abridgement in Campbell and Sowden 1985: pp. 133?58.)
4. Hurley, S. L.: 1989, Natural Reasons: Personality and Polity, Oxford University Press, New York.
5. Jeffrey, R. C.: 1981, ?The Logic of Decision Defended?, Synthese 48, 473?92.