Knapp, C. L. (1976). Problems in Contract Law: Cases and Materials. Little Brown & Co.
Lua i Stíl Chicago (17ú heag.)Knapp, Charles L. Problems in Contract Law: Cases and Materials. Boston: Little Brown & Co, 1976.
Lua MLA (9ú heag.)Knapp, Charles L. Problems in Contract Law: Cases and Materials. Little Brown & Co, 1976.
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