Ya'ish ibn Ibrahim al-Umawi

Abū ʿAbdallāh Yaʿīsh ibn Ibrāhīm ibn Yūsuf ibn Simāk al-Andalusī al-Umawī (Arabic: يعيش بن إبراهيم بن يوسف بن سماك الأموي الأندلسي) (1400? in Al-Andalus – 1489 in Damascus, Syria) was a 15th-century Spanish-Arab[1] 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).

References

Gibb, Hamilton Alexander Rosskeen; Kramers, Johannes Hendrik; Lewis, Bernard; Pellat, Charles; Schacht, Joseph (1970). The Encyclopaedia of Islam. Brill.

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.
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., "Ya'ish ibn Ibrahim al-Umawi", MacTutor History of Mathematics Archive, University of St Andrews

Mathematics Encyclopedia