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2. Hajek, John (1997) Universals of Sound Change in Nasalization, Blackwell, Oxford.
3. Jespersen, Otto (1909) A Modern English Grammar, Part I, Munksgaad, Copenhagen.
4. Jones, Charles (1989) A History of English Phonology, Longman, London.
5. Jordan, Richard and Eugene J. Crook (1974) Handbook of Middle English Grammar, Mouton, The Hague.