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Lua i Stíl Chicago (17ú heag.)SIMPSON, Ormond. Student Retention in Online, Open and Distance Learning. Kogan page, 2003.
Lua MLA (9ú heag.)SIMPSON, Ormond. Student Retention in Online, Open and Distance Learning. Kogan page, 2003.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.