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Sixth century Chinese philologist
沈重 Shěn Zhòng is a sixth-century Chinesephilologist. In his commentary of the Book of Songs he was the first scholar to note that the poems did not rhyme in contemporary pronunciation. He suggested pronouncing words differently in order to make the rhymes work. This practice is referred to as xíe yùn.
References
Baxter, William. Handbook of Old Chinese Phonology. Berlin: Mouton, p. 152