↑Zhou, Yimin (2002). 现代北京话研究. Beijing Normal University Press. hlm.202. ISBN7-303-06225-4.
↑Hammarström, Harald; Forkel, Robert; Haspelmath, Martin, ed. (2023). "Beijing Mandarin". Glottolog 4.8. Jena, Jerman: Max Planck Institute for the Science of Human History. ; ;