Calamari, John D.
Contracts
West Publishing, 1990
 Buku Teks
Farnsworth, E. Allan
Contracts
Little, Brown, 1990
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Schaber, Gordon D.
Contracts in a nutshell
West Publishing, 1990
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Waddams, S.M.
The Law of Contracts
Canada Law Book INC, 1984
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Rohwer, Claude D.
Contracts in a nutshell
Thomson Reuters, 2010
 Buku Teks