* {{citeCite book|authorref=-{Ewan harv|last=McKendrick|first=Ewan|title=Contract Law - Text, Cases and Materials|location=|publisher=Oxford University Press}|year=2005|isbn=978-0-19-927480-2|pages=}}
* {{citeCite book|ref= harv|author=-{P.S. Atiyah|title=The Rise and Fall of Freedom of Contract|location=|publisher=Clarendon Press}|year=1979|isbn=978-0-19-825342-6|pages=}}
* {{citeCite book|authorref= harv|last=Barnett|first=-{Randy E. Barnett|title=Contracts|location=|publisher=Aspen Publishers}|year=2003|isbn=978-0-7355-6525-8|pages=}}
* -{Scott Fruehwald, "Reciprocal Altruism as the Basis for Contract," 47 University of Louisville Law Review 489 (2009).}-
