Iorwerth ap Dafydd

See Peter Bartrum, https://cadair.aber.ac.uk/dspace/bitstream/handle/2160/4808/cadwgon... (February 12, 2020; Anne Brannen, curator)

Please see Darrell Wolcott: Bartrum's "Pedigrees of the Welsh Tribal Patriarchs"' # 4 Cadwgan Fantach; http://www.ancientwalesstudies.org/id172.html. (Steven Ferry, September 7, 2019.)

Please see Darrell Wolcott: The Royal Family of Gwynedd - Einion ap Llywarch of Carmarthenshire; http://www.ancientwalesstudies.org/id163.html. (Steven Ferry, January 22, 2020.)

Please see Peter Bartrum: Rhydderch ap Tewdwr 5; https://www.geni.com/documents/view?doc_id=6000000173392303854 & Cadwgon Fantach; https://www.geni.com/documents/view?doc_id=6000000173385163829 (Steven Ferry, November 29, 2024.)