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2. Bauer, Laurie (1994) Watching English Change, Longman, London and New York.
3. Beard, Adrian (2004) Language Change, Routledge, London and New York.
4. Bybee, Joan L. and William Pagliuca (1985)“Cross-linguistic Comparison and the Development of Grammatical Meaning,”Historical Semantics and Historical Word Formation, ed. by Jack Fisiak, 59-83, Mouton de Gruyter, Berlin.
5. Givón, Talmy (1979) On Understanding Grammar, Academic Press, New York.