Rhyfel Mawr

== Welsh == === Proper noun === y Rhyfel Mawr m the Great War, the First World War Synonym: y Rhyfel Byd Cyntaf === Mutation === === Further reading === R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke, et al., editors (1950–present), “Rhyfel Mawr”, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies