From: Hachmeier, Klaus U. Private Letters, Official Correspondence:Buyid Insha as a historical source, Journal of Islamic studies, Oxford center for Islamic studies, 2002, PP. 125 – 154.

Hachmeier, K. U., & Yahyaei, R. A. (2008). From: Hachmeier, Klaus U. Private Letters, Official Correspondence:Buyid Insha as a historical source, Journal of Islamic studies, Oxford center for Islamic studies, 2002, PP. 125 – 154.. History of Islam, 9(Issue 33 , 34), 227-274.

Klaus U Hachmeier; Rajad ali Yahyaei. "From: Hachmeier, Klaus U. Private Letters, Official Correspondence:Buyid Insha as a historical source, Journal of Islamic studies, Oxford center for Islamic studies, 2002, PP. 125 – 154.", History of Islam, 9, Issue 33 , 34, 2008, 227-274.

Hachmeier, K. U., Yahyaei, R. A. (2008). 'From: Hachmeier, Klaus U. Private Letters, Official Correspondence:Buyid Insha as a historical source, Journal of Islamic studies, Oxford center for Islamic studies, 2002, PP. 125 – 154.', History of Islam, 9(Issue 33 , 34), pp. 227-274.

Hachmeier, K. U., Yahyaei, R. A. From: Hachmeier, Klaus U. Private Letters, Official Correspondence:Buyid Insha as a historical source, Journal of Islamic studies, Oxford center for Islamic studies, 2002, PP. 125 – 154.. History of Islam, 2008; 9(Issue 33 , 34): 227-274.