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Similar examples abound. Macedonian, although mutually intelligible with Bulgarian, certain dialects of Serbian and to a lesser extent the rest of the South Slavic dialect continuum, is considered by Bulgarian linguists to be a Bulgarian dialect, in contrast with the contemporary international view and the view in the Republic of Macedonia, which regards it as a language in its own right. Nevertheless, before the establishment of a literary standard of Macedonian in 1944, in most sources in and out of Bulgaria before the Second World War, the southern Slavonic dialect continuum covering the area of today's Republic of Macedonia were referred to as Bulgarian dialects.

Along with Serbian, with what language is Macedonian mutually intelligible?
Bulgarian