Howatt, Anthony Philip Reid; Widdowson, Henry George: A History of English Language Teaching. Oxford University Press (2004), pp. 198–207. ISBN0-19-442185-6 (Online text)
The Oldest English Texts, ed. Henry Sweet (London: EETS, 1885), p. v. See further Richard Utz, Chaucer and the Discourse of German Philology (Turnhout: Brepols, 2002), pp. 67-69.
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