1. Y rhagenwau ôl yng ngherddi’r Gogynfeirdd;Andrews Rhian M.;Bulletin of the Board of Celtic Studies,1989
2. On some Middle Welsh relative constructions;Armstrong John;Studia Celtica,1987
3. Middle Welsh 1sg. pres. ind. oef “I am” and early southern Welsh orthography;Band Linus;Studia Celtica,2015