The Cambridge History of Iran
. — The Cambridge History of Iran. Vol. 5. The Saljuq and Mongol Periods. Ed. by J. A. Boyle. Cambridge, 1968.Hudud
. — Hudud al-'atam: The Regions of the World, a persian geography 372 A. H. — 982 A. D. Transl. and explained by V. Minorsky. L., 1937.