Abu'l-Hasan al-Uqlidisi

Abū al-Ḥassan, Aḥmad Ibn Ibrāhīm, al-Uqlīdisī was a Muslim Arabmathematician of the Islamic Golden Age, possibly from Damascus, who wrote the earliest surviving book on the use of decimal fractions with Hindu–Arabic numerals, Kitāb al-Fuṣūl fī al-Ḥisāb al-Hindī, in Arabic in 952. The book is well preserved in a single 12th-century manuscript, but other than the author's name, original year of publication and the place (Damascus) we know nothing else about the author: after an extensive survey of extant reference material, mathematical historian Ahmad Salīm Saʿīdān, who discovered the manuscript in 1960, could find no other mention of him. His nickname al-Uqlīdisī was commonly given to people who sold manuscript copies of Euclid's Elements.