"Celtic language" . . . "disappeared" . "PCelt" . . "Proto-Celtic language" . . "Common Celtic" . . "Celtic" . . "Morphology of the Proto-Celtic language" . "Early Celtic" . "n-stem" . . "P-Celtic" . "Proto-Celtic nasal stem" . . "Pre-Celtic" . "Celtic languages" . . "proto-Celtic language" . "Proto-Eastern-Celtic" . "Proto-Celtic form" . . "Proto-Celts" . . "proto Celtic" . "Old Celtic" . "Proto-Celtic" . "proto-Celtic" . . "Q-Celtic" . . . . "Proto-Celtic language" .