MICHAEL KENNEDY and JOYCE BOURNE. "Tibbett (Tibbet), Lawrence (Mervil)." The Concise Oxford Dictionary of Music. 1996. Encyclopedia.com. 16 Nov. 2009 <http://www.encyclopedia.com>.
MICHAEL KENNEDY and JOYCE BOURNE. "Tibbett (Tibbet), Lawrence (Mervil)." The Concise Oxford Dictionary of Music. 1996. Encyclopedia.com. (November 16, 2009). http://www.encyclopedia.com/doc/1O76-TibbettTibbetLawrenceMrvl.html
MICHAEL KENNEDY and JOYCE BOURNE. "Tibbett (Tibbet), Lawrence (Mervil)." The Concise Oxford Dictionary of Music. 1996. Retrieved November 16, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O76-TibbettTibbetLawrenceMrvl.html