c1 is an autonym (self-given name) of c2=c3.
May be a collective name, such as Diné, the endonym of the Navajo/Naabeehó people; or may be an individual's self-given name. Not synonymous with "local name" as in English. Potentially synonymous with nerme'e, (which more closely translates "endonym", morpheme-for-morpheme, rather than "autonym"). An exonym or external name might be called barme'e.