See Peter Bartrum, https://www.geni.com/documents/view?doc_id=6000000173392791993 (October 1, 2022; Anne Brannen, curator)

Please see Darrell Wolcott: Pedigree of Madog ap Idnerth; http://www.ancientwalesstudies.org/id267.html; [#105]. (Steven Ferry, June 19, 2021.)

Please see Darrell Wolcott: The Royal Family of Powys - The "Mael Maelienydd" in Medieval Pedigrees; http://www.ancientwalesstudies.org/id76.html. (Steven Ferry, April 17, 2023.)