《资治通鉴·梁纪·梁纪十四》
头兵可汗曾经到过洛阳，心里仰慕中原，就按照北魏的官制设置了侍中、黄门等官职；后来他得到了北魏汝阳王的典签淳于覃，非常亲近宠信，十分重用，委任为秘书监，使其主管文书。
头兵尝至洛阳，心慕中国，乃置侍中、黄门等官；后得魏汝阳王典签淳于覃，亲宠任事，以为秘书监，使典文翰。
Chief Biling Khan had visited Luoyang in the past, and since he admired the Central Plains, he adopted part of the Northern Wei official system and established positions such as Shizhong and Huangmen. Later, he acquired Chunyü Tan, who had been an Imperial Attendant of Ruyin Wang of Northern Wei, as a retainer. He was deeply attached and loyal to Chief Biling Khan and was highly respected by him. He was appointed as Secretary in Charge of Documents and Archives and put in charge of official correspondence.