Seferws ap Cadwr, Lord of Builth

See Peter Bartrum, https://cadair.aber.ac.uk/dspace/bitstream/handle/2160/6516/TABLES%... (May 31, 2018; Anne Brannen, curator)

See Peter Bartrum, https://cadair.aber.ac.uk/dspace/bitstream/handle/2160/6516/TABLES%... (May 29, 2018; Anne Brannen, curator)

See Darrell Wolcott, the Pedigree of Cynddelw Gam, for the untangling of these lines: http://www.ancientwalesstudies.org/id94.html (March 1, 2016; Anne Brannen, curator).

Please see Darrell Wolcott: Bartrum's "Pedigrees of the Welsh Tribal Patriarchs" #14 Mam Tudor Trefor; http://www.ancientwalesstudies.org/id182.html. (Steven Ferry, September 20, 2019.)

Please see Darrell Wolcott: The Shropshire Walcot Family - Chart II: Second Powys Dynasty; http://www.ancientwalesstudies.org/id99.html. (Steven Ferry, May 14, 2020.)

Please see Darrell Wolcott: The Enigmatic Elystan Glodrydd; http://www.ancientwalesstudies.org/id199.html. (Steven Ferry, August 11, 2020.)

Please see Darrell Wolcott: The Unofficial "History" of Elystan of Powys; http://www.ancientwalesstudies.org/id230.html. (Steven Ferry, August 12, 2020.)

Please see Darrell Wolcott: The Clan of Tudor Trevor; http://www.ancientwalesstudies.org/id55.html. (Steven Ferry, May 5, 2022.)