Tangwystl verch Owain, Heiress of Dyfed

See Peter Bartrum, https://www.geni.com/documents/view?doc_id=6000000173393650888 (February 6, 2023; Anne Brannen, curator)

Please see Darrell Wolcott: Rulers of Brycheiniog - The Unanswered Questions; http://www.ancientwalesstudies.org/id161.html. (Steven Ferry, March 17, 2020.)

Please see Darrell Wolcott: The Legendary Kingdom of Seisyllwg; http://www.ancientwalesstudies.org/id123.html. (Steven Ferry, September 11, 2020.)

Please see Darrell Wolcott: Harleian Ms 3859; http://www.ancientwalesstudies.org/id129.html. (Steven Ferry, March 8, 2021.)

Please see Darrell Wolcott: Hyfaidd ap Bleddri versus Sons of Rhodri Mawr; http://www.ancientwalesstudies.org/id266.html. (Steven Ferry, May 5, 2021.)