The Peter de Ridder Press, 1976. — 155 p. — (PdR Press publications in comparative Romance linguistics 1).
The classification of the Romance languages has been a long-standing object of interest for scholars in Romance Linguistics. This concern with classification stems essentially from efforts to establish the history of a language. Where a language, or dialect, is moot on a particular point, a development found in a 'closely related' language may be posited for it. Diachronically, close relationship is determined by shared phonemic changes. However, languages may be found which are 'ambivalent', i.e. they can be shown to share phonemic changes with either language A or language B, which in turn are known to have separate developments. In studies which use vowel development as the basis classificatory criterion, Sicilian is an ambivalent language, since it can be grouped either with Italian or with Sardinian.