Abdulquader, Osama. " The Civilized Contributions for the Mua’thins (Callers for Prayer) of Nisapur in the Third and the Fourth Centuries A.H." Journal of Tikrit university for humanities - مجلة جامعة تكريت للعلوم الانسانية [Online], Volume 27 Number 8 (30 December 2020)