Charles Ferguson first proposed the Ethiopian language area (1970, 1976). (Various scholars may also use the terms Sprachbund or linguistic area.) He posited a number of phonological and morpho-syntactic features that were found widely across Ethiopia (which included Eritrea at that time), including the Ethio-Semitic, Cushitic, and Omotic languages, but it did not include the Nilo-Saharan languages. Since then, others have pointed out smaller areas of shared features within this larger area (Appleyard 1989, Breeze 1988, Sasse 1986, Tosco 1994, Wedekind 1989).