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Charles W. Jones 'þe' and 'pat' as Clause Connectives in Early Middle English with Especial Consideration of the Emergence of the Pleonastic þat; The Pleonastic That in Relative and Interrogative Constructions in Chaucer's Verse. Commentationes Humanarum Litterarum, Societas Scientiarum Fennice, Vol. 39, Nos. 1 and 3, by Kirsti Kivimaa 37.3 (1968), 328-332 DOI:10.2307/43627478
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