Ithel Hael or Ithel Hael o Lydaw was a prince of Armorica who lived in the early part of the sixth century. He was the father of Baglan, Flewyn, Gredifael, Tanwg, Twrog, Tegai, Trillo, Tecwyn and Llechid, saints who accompanied Cadfan to Britain.
- Enwogion Cymru A Biographical Dictionary of Eminent Welshmen, from the Earliest Times to the Present, and Including Every Name Connected with the Ancient History of Wales By Robert Williams, Llandovery, 1852. URL: http://books.google.co.uk/books?id=_wMGAAAAQAAJ
- The Lives of the British Saints: The Saints of Wales, Cornwall and Irish Saints By S. Baring-Gould, John Fisher, Honourable Society of Cymmrodorion (London, England) Edition: illustrated Published by Kessinger Publishing, 2005, ISBN 0-7661-8767-5. URL: http://books.google.co.uk/books?id=0jLjYgygkB0C