Williams, Stephen J.: A welsh grammar, 1980. University of Wales Press. ISBN: 0-7083-0735-3.
Davies, Janet: The Welsh Language, 1993. University of Wales Press.
Williams, Gwyn: An Introduction to Welsh Literature, 1992. University of Wales Press, Cardiff .
Thomas, W. O., Meurig Evans H., Y Geiriadur Mawr: The New Welsh to English and English to Welsh Dictionary, 2007. Gwasg Dinefwr a Gwasg Gomer.
Evans, S.: A Grammar of Middle Welsh, 1964. The Dublin Institute for Advanced Studies.
Kompendium
T. Arwyn Watkins, Welsh & Robert Owen Jones: The sociolinguistics of Welsh , (Kap. 7 og 12) i Martin J. Ball & James Fife (ed.), _The Celtic Languages_. Routledge 1993 .