APA (7th ed.) Zitazioa
Knowles, R. (2005). 150 contractual problems and their solutions. Blackwell Pub..
Chicago Style (17th ed.) Zitazioa
Knowles, Roger. 150 Contractual Problems and Their Solutions. Oxford ; Malden, MA: Blackwell Pub., 2005.
MLA (9th ed.) Zitazioa
Knowles, Roger. 150 Contractual Problems and Their Solutions. Blackwell Pub., 2005.
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