1. 2024
2. 'Os gwêl Bangor ei debyg eto, bydd gwyn ei byd': Golwg ar gyfraniad J. Lloyd Williams fel Cyfarwyddwr Cerdd a Chyfansoddwr rhwng 1897 a 1914

   Keen, E. (Author), Thomas, W. (Supervisor), Rees, S. (Supervisor) & Ap Sion, P. (Supervisor), 15 Mar 2024

   Student thesis: Doctor of Philosophy

3. 2023

4. Nada Brahman: Pandit Pran Nath and La Monte Young, Terry Riley, Rhys Chatham and Michael Harrison

   Boas, L. (Author), ap Sion, P. (Supervisor) & Cunningham, J. (Supervisor), 31 Mar 2023

   Student thesis: Masters by Research

5. The Tune is the Nation’s: Astudiaeth o Drefniannau Alawon Gwerin Cymreig Grace Williams

   Jones, E. (Author), Llewelyn Jones, I. (Supervisor) & ap Sion, P. (Supervisor), 16 Jan 2023

   Student thesis: Masters by Research

6. 2022
7. The Adaptable Composer: Context and Collaboration: A portfolio of compositions

   Roberts, C. (Author), ap Sion, P. (Supervisor) & Puw, G. (Supervisor), 3 Feb 2022

   Student thesis: Doctor of Philosophy

8. 2020
9. Waiting room

   Hughes, T. (Author), ap Sion, P. (Supervisor), 15 Jun 2020

   Student thesis: Masters by Research

10. 2015

11. Multiples of the same : a semiotic study of Steve Reich's Counterpoint series

    Bakker, T. (Author), Collins, C. (Supervisor) & ap Sion, P. (Supervisor), Jan 2015

    Student thesis: Doctor of Philosophy