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Lua i Stíl Chicago (17ú heag.)DIRECTOR, Stephen W. Introduction To Systems Theory Tephen W. Director. McGraw-Hill, 1972.
Lua MLA (8ú heag.)DIRECTOR, Stephen W. Introduction To Systems Theory Tephen W. Director. McGraw-Hill, 1972.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.