| title | ISBN-13 | year of publica- tion | other author(s) |
|---|---|---|---|
| A dictionary of Old Breton =: Dictionnaire du vieux breton: historical and comparative: in two parts | 978-0-9692225-0-7 | 1985 | |
| Les origines de la bretagne | 978-2-228-12711-0 | 1980 | Leon Fleuriot |
| Les origines de la Bretagne: L'émigration | 978-2-228-12710-3 | 1980 | |
| Le vieux breton | 978-2-05-101059-7 | 1989 | |