O'Connor, John J.; Robertson, Edmund F. «Arabic mathematics: forgotten brilliance?» (en anglès). MacTutor History of Mathematics archive. School of Mathematics and Statistics, University of St Andrews, Scotland.
O'Connor, John J.; Robertson, Edmund F. «Al-Sabi Thabit ibn Qurra al-Harrani» (en anglès). MacTutor History of Mathematics archive. School of Mathematics and Statistics, University of St Andrews, Scotland.
O'Connor, John J.; Robertson, Edmund F. «Omar Khayyam» (en anglès). MacTutor History of Mathematics archive. School of Mathematics and Statistics, University of St Andrews, Scotland.