Lot Essay
Kitab al-Istibsar is one of the four canonical manuals on hadith for Shi'i Islam. It was composed by Muhammad bin al-Hasan bin 'Ali al-Tusi (d. 1067 AD), a mufassir from Khurasan who moved to Baghdad and then to Najaf where he died (see Al-Zerekly, Al-A'lam, Biographic Dictionary, Beirut, 2007, vol. II, p.84).