Ibn Khordadbeh
Discussing their relationship with Karluks, Minorsky and Golden noted that the Khalaj and Karluks were often confused by medieval Muslim authors, as their names were transcribed almost similarly in Arabic. Even so, Kitāb al-Masālik w’al- Mamālik's author Ibn Khordadbeh distinguished Khalajs from Karluks, though he mentioned that both groups lived beyond the Syr Darya of the Talas; Muhammad ibn Najib Bakran wrote in his "Jihān-nāma" (c. 1200-20) that "by mistake (in writing) the people called the Khallukh "Khalaj"."