DONZEL, Emeri „van“. Islamic Reference Desk. [s.l.]: Brill Academic Publishers, 1994. Dostupné online. S. 461. (anglicky) Iranian term applied to region lying to the northeast of Iran and ultimately indicating very vaguely the country of the Turkic peoples..
K. H. Menges, in Encyclopaedia IranicaArchivováno 17. 5. 2008 na Wayback Machine. Excerpt: "In a series of relatively minor movements, Turkic groups began to occupy territories in western Central Asia and eastern Europe which had previously been held by Iranians (i.e., Turan). The Volga Bulgars, following the Avars, proceeded to the Volga and Ukraine in the 6th-7th centuries."
medievalists.net
http://www.medievalists.net/2009/01/04/barbarian-incursions-the-coming-of-the-turks-into-the-islamic-world/ Bosworth, C. E. "Barbarian Incursions: The Coming of the Turks into the Islamic World." In Islamic Civilization, Edited by D. S. Richards. Oxford, 1973. pg 2: "Hence as Kowalski has pointed out, a Turkologist seeking for information in the Shahnama on the primitive culture of the Turks would definitely be disappointed."
K. H. Menges, in Encyclopaedia IranicaArchivováno 17. 5. 2008 na Wayback Machine. Excerpt: "In a series of relatively minor movements, Turkic groups began to occupy territories in western Central Asia and eastern Europe which had previously been held by Iranians (i.e., Turan). The Volga Bulgars, following the Avars, proceeded to the Volga and Ukraine in the 6th-7th centuries."