Note on Welsh language from Wikipedia.
Notes on Welsh language from : Pallas Wales, by Sayre.
Various tables on Welsh words. Glossaries.
Notes on the pronunciation. (Welsh)
The Mother Tongue. From: U.S. News and World Report, Nov. 5, 1990.
The glossaries are very useful in understanding some of the Welsh naming which is often the key to documenting and identifying certain individuals.
For a discussion of Welsh genealogy see: http://welshgenealogy.blogspot.com .