APA (7th ed.) Zitazioa
De Jasay, A. (2008). Social contract, free ride: A study of the public-goods problem. Liberty Fund.
Chicago Style (17th ed.) Zitazioa
De Jasay, Anthony. Social Contract, Free Ride: A Study of the Public-goods Problem. Indianapolis, Ind.: Liberty Fund, 2008.
MLA (9th ed.) Zitazioa
De Jasay, Anthony. Social Contract, Free Ride: A Study of the Public-goods Problem. Liberty Fund, 2008.
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