Omar Khayyam, Encyclopædia Britannica 2007 http://www.britannica.com/eb/article-9057079/Omar-Khayyam accessdate =2007-06-09
Gives his name as Ghiyath al-Din Abu al-Fath 'Umar ibn Ibrahim al-Nisaburi al-Khayyami (the last two differ from the version here), and lists mathematician before poet in his identity.
