- NLW ex 1909
- File
Manuscript of 'Mari Wynne a'r Pedwerydd Dosbarth' by the author Eluned Jones written after she completed a year's course on bilingualism at the Faculty of Education in Aberystwyth, and which includes the observations of Professor Jac L. Williams; it was later published under the title Helyntion y pedwerydd dosbarth (Llandybïe, 1967).