Covington, G. A. (1997). Access By Design George A. Covington, Bruce Hannah. Van Nostrand Reinhold.
Lua i Stíl Chicago (17ú heag.)Covington, George A. Access By Design George A. Covington, Bruce Hannah. Van Nostrand Reinhold, 1997.
Lua MLA (8ú heag.)Covington, George A. Access By Design George A. Covington, Bruce Hannah. Van Nostrand Reinhold, 1997.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.