Abu Bishr Isma'il ibn Ibrahim ibn Muqsim (Arabic: أبو بشر إسماعيل بن إبراهيم بن مِقْسَم ;729 – 809 CE), commonly known as Ibn 'Ulayya (Arabic: ابن عُليَّة), was a hadith scholar, faqih and a mufti from Basra. During the reign of Harun ar-Rashid, he was tax collector and later judge in Basra, where he died in 193 H (809 AD). Source: Wikipedia (en)