Simon Roper | 'Gutteral' Sounds (Back Fricatives) in English @simonroper9218 | Uploaded September 2021 | Updated October 2024, 1 day ago.
Lass, R. 1999. The Cambridge History of the English Language, Vol III.

Paston letters on Archive.org - archive.org/details/pastonletters01arbeiala/page/548/mode/2up

Hart, J. 1569. An Orthographie.

Butler, C. 1633. English Grammar.

Brilioth, B. 1913. A Grammar of the Dialect of Lorton (Cumberland).

Wheeler, A. 1790. The Westmorland Dialect in Three Familiar Dialogues.

Warren Maguire's fantastic mapping of some of the findings of Alexander Ellis's 1889 survey: lel.ed.ac.uk/EllisAtlas/Vowels.html


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