Heinz Kloss 1967, "Abstand languages and Ausbau languages" in Anthropological Linguistics (Harvard : Harvard Press)
----------------------------------------
Dachsprache ['roof language'] means a language form that serves as standard language for different dialects, mostly in a dialect continuum, even though these dialects may be so different that mutual intelligibility is not possible on the basilectal level between all dialects, particularly those separated by significant geographical distance.
Kloss has also used the term pseudo-dialectized abstand language for cases where a variety is so different from its Dachsprache that it ought to be regarded as a separate language on abstand grounds, but is nevertheless treated more like a dialect in social practice.