Biography:Yaʿīsh ibn Ibrāhīm al-Umawī

Abū ʿAbdallāh Yaʿīsh ibn Ibrāhīm ibn Yūsuf ibn Simāk al-Andalusī al-Umawī (1400? in Al-Andalus – 1489 in Damascus, Syria) was a 14th-century Spanish-Arab mathematician.

Works

• Marasim al-intisab fi'ilm al-hisab ("On arithmetical rules and procedures"), first date written in 1373 and hence the birth date above is controversial.
• Raf'al-ishkal fi ma'rifat al-ashkal (a work on mensuration).

Bibliography

• Saidan, A. S. (1970). "Al-Umawī, Abū ‘Abdallāh Ya‘īsh Ibn ibrāHīm Ibn Yūsuf Ibn Simāk Al-Andalusī". Dictionary of Scientific Biography. New York: Charles Scribner's Sons. ISBN 0-684-10114-9. http://www.encyclopedia.com/doc/1G2-2830904415.html. 
• Ahmad Salim Saidan (ed.), Yaish ibn Ibrahim al-Umawi, On arithmetical rules and procedures (Aleppo, 1981).

External links

• O'Connor, John J.; Robertson, Edmund F., "Yaʿīsh ibn Ibrāhīm al-Umawī", MacTutor History of Mathematics archive, University of St Andrews, http://www-history.mcs.st-andrews.ac.uk/Biographies/Al-Umawi.html .