Catholic Encyclopedia: St. Gildas - - Biographical entry for St. Gildas the Wise, also called "Badonicus," born to a British family in Scotland, educated in Wales, monk, priest, died in 570. http://www.newadvent.org/cathen/06557c.htm
Gildas - - Profile of the saint. With links. http://saints.sqpn.com/saintg31.htm
Gildas Badonicus - - A commentary by John Morris on the 6th-century author, a summary by Frank Reno of the confusions with others of the same name, the 11th-century and 12th-century lives and the Giles translation of De Excidio Brittaniae et Conquestu. http://celtic-twilight.com/camelot/gildas/
Gildas the Wise - - Biographical profile, by Karen Rae Keck. http://www2.evansville.edu/ecoleweb/glossary/gildas.html
St. Gildas Badonicus - - Biography by David Nash Ford of the 6th-century author of "De Excidio Britanniae," drawing on the dubious 11th-century life by a monk of Rhuys. http://www.earlybritishkingdoms.com/bios/gildas.html
Vietnamese Eucharistic Youth Society: St. Gildas - - The story of St. Gildas the Wise, suited to children. Preformatted line breaks can make this difficult to read. http://www.tntt.org/vni/tlieu/saints/St0129.htm