Ibn Hawqal
Professor Ighrar Aliyev also mentions that the Arab historians Baladhuri, Masudi, Ibn Hawqal and Yaqut have mentioned this language by name. Medieval historians and scholars also record that the language of the region of Azerbaijan, as well as its people there, as Iranians who spoke Iranian languages. Among these writes are Al-Istakhri, Al-Masudi, Ibn al-Nadim, Hamzeh Esfahani, Ibn Hawqal, Al-Baladhuri, Moqaddasi, Yaghubi, Hamdallah Mostowfi, and Al-Khwarizmi.