Zograph, G.A. (8 de marzo de 2023). Languages of South Asia: A guide. Taylor & Francis. ISBN9781000831658. «Numerically, the content of the Central Group of the Indo-Aryan languages has been very variously assessed by different researchers: Chatterji sees in it one language while Grierson enumerated six. Strictly speaking, the core of this group is represented not by languages at all, but by a number of closely related dialects-Braj, Kanauji and Bundell, which together with Khari Boli and Hariani, can be lumped under the common title 'Western Hindi'. The last-mentioned two dialects which occupy the north-western corner of the area covered by Hindi, display a number of common features with Panjabi, which in its turn can be seen as a transitional link with the most typical representative of the North Western group – Lahnda.
Closely connected with the dialects of the 'Western Hindi' group are Awadhi, Bagheli and Chattisgarhi, which come under the heading of 'Eastern Hindi". Linguistically, these can be regarded as a transitional stage between the Central and the Eastern groups of languages. The 'intermediate' character of this group of dialects seems to have taken shape as far back as the Old Indo-Aryan period. The Middle Indo-Aryan forerunner of the contemporary Eastern Hindi dialects was the Ardhamagadhi Prakrit, which was a transitional form between Sauraseni and Magadhi; the present-day Central dialects go back to Sauraseni, while the languages of the Eastern group derive from Magadhi».
