John Williams, The Ecclesiastical Antiquities of the Cymry; Or the Ancient British Church; Its History, Doctrine, and Rites. (John WILLIAMS (M.A., Rector of Llanymowddwy). 1844) page 112.
Irish Archaeological and Celtic Society, Irish Archaeological and Celtic Society Publications (Irish Archaeological and Celtic Society, 1848) page 104.
William Owen Pughe, The Cambrian Biography: Or, Historical Notices of Celebrated Men Among the Ancient Britons (William Owen Pughe, 1803) page 3.
Rev. Rice Rees, An Essay on the Welsh Saints or the Primitive Christians who were Founders of churches in Wales (Longman, 1836) page 132.