‡ denotes primary source study
Apfel, Ernst. 1959. Studien zur Satztechnik der mittelalterlichen englischen Musik. 2 vols.
Pages: chapter 1 and opening of chapter 2 up to p. 63.
Dittmer, Luther A. 1959. Publications of Mediaeval Musical Manuscripts V: Worcester Add. 68, Westminster Abbey 33327, Madrid Bibl. Nac. 192. Publications of Mediaeval Music Manuscripts. Brooklyn: Institute of Mediaeval Music.
Harrison, Frank Llewellyn. 1958, second ed. 1963. Music in Medieval Britain. London: Routledge.
Pages: 132ff.
Dittmer, Luther A. 1957. The Dating and the Notation of the Worcester Fragments. Musica Disciplina, 5-11.
Dittmer, Luther A. 1957. Auszug aus The Worcester-Music-Fragments.
Dittmer, Luther A (editor). 1957. The Worcester Fragments: A Catalogue Raisonné and Transcription, s.l. Musicological Studies and Documents. Neuhausen nr. Stuttgart: American Institute of Musicology.
Pages: introduction.
Dittmer, Luther A. 1954. An English Discantuum Volumen. Musica Disciplina, 19ff.
Pages: 29ff.
Dittmer, Luther A. 1953. Binary Rhythm, Musical Theory and the Worcester Fragments. Musica Disciplina, 39-57.
Levy, K J. 1951. New material on the early motet in England. A Report on the Princeton MS. Garrett 119. Journal of the American Musicological Society, 220-239.
Handschin, Jacques. 1949. The Summer Canon and its Background. Musica Disciplina, 55-94, volume 5 (1951), 65-113.
Pages: II, 66ff.
Bukofzer, Manfred F. 1944. "Sumer is icumen in": A Revision. .
Reese, Gustave. 1940. Music in the Middle Ages: With an introduction on the music of ancient times. New York: W.W. Norton & Co.
Hughes, Dom Anselm. 1928. Worcester Mediaeval Harmony of the Thirteenth and Fourteenth Centuries. Burnham: Plainsong and Mediaeval Music Society.
Ludwig, Friedrich (editor). 1926-9. Guillaume de Machaut: Musikalische Werke, 1-3. Leipzig: Publikationen älterer Musik.
Pages: II, 34, 62.
Besseler, Heinrich. 1925. Studien zur Musik des Mittelalters: I. Neue Quellen des 14. und beginnenden 15. Jahrhunderts. Archiv für Musikwissenschaft, 167-252.
Pages: I, 219ff.
Ludwig, Friedrich. 1923. Die Quellen der Motetten ältesten Stils. Archiv für Musikwissenschaft, 185-222, Vol. 5 (1924) 273-315.
Pages: 191, 274.
Floyer, J K, and S G Hamilton. 1906. Catalogue of Manuscripts Preserved in the Chapter Library of Worcester Cathedral.
Wooldridge, Harry Ellis, and H V Hughes (editors). 1897 and 1913. Early English Harmony from the 10th to the 15th Century. 2 vols. London: The Plainsong and Medieval Music Society.