Obaid Issa, Ahmed, AND 		Ali Saud Al-Jubouri, Abdullah.
" Diwan Al-Kharaj and Al-Ataa Al-Nashra and Development until the end of the Umayyad era" <em>Journal of Tikrit university for humanities - مجلة جامعة تكريت للعلوم الانسانية</em> [Online], Volume 23 Number 4 (31 March 2019)