ABŪ MANṢŪR ṬŪSĪ, mathematician. Apparently sometime during the 9th/15th century Abū Manṣūr wrote two works preserved in a manuscript at Florence: 1. Resāla fī ʿelm al-ḥesāb (“Epistle concerning computation”); 2. Resāla fi’l-ǰabr wa’l-moqābala (“Epistle concerning algebra”).