An Old-Irish metrical rule (1904). An anonymous poem concerning the rule of the Lord, or Comgall's rule, written c. 800, transcribed by John Strachan. In Ériu, Volume I (1904). pp. 191–208.
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Webb, Alfred
"Saint Comgall", A compendium of Irish Biography, 1878.
MacCaffrey,James (1908). "St. Comgall". In Catholic Encyclopedia. 4. New York: Robert Appleton Company. This article incorporates text from this source, which is in the public domain.