^Hammarström, Harald; Forkel, Robert; Haspelmath, Martin; Bank, Sebastian, eds. (2016). "Longqu". Glottolog 2.7. Jena: Max Planck Institute for the Science of Human History.
^Charles Bazerman (2009). Charles Bazerman, ed. Traditions of writing research (illustrated ed.). Taylor & Francis. p. 154. ISBN0-415-99337-7. Retrieved 4 November 2011. Method Participants Eighty-four children participate in the study: 28 Chinese children, mostly from Zhejiang—a province south to Shanghai, speakers of Qing Tian Hua; 26 Moroccan children mostly from North Morocco, speakers of Darija— ie, Moroccan Arabic;