Thomas Malory's Le Morte d'Arthur, composed in the middle of the 15th century, and published in 1485 by William Caxton, is the version of the Arthurian legend that became the foundation for most of the treatments of the legend known now -- White's The Once and Future King, for instance, upon which the musical Camelot is based, and Tennyson's Idylls of the King. Malory's work is an amalgamation of several earlier Arthurian texts, including both French and English sources, and adds some original material. The work is readily available in print; an e-version can be found here:

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