One more thing, even if we accept the view that Vlachs of Serbia are part of the Romanians of Serbia, that still does not mean that we should to merge this article into "Romanians of Serbia" because of the same reason why article "Romanians of Serbia" is not merged into article "Romanians". Another example is that we have articles about Magyars, about Szekely (part of Magyars), and about Szekely of Bukovina (part of Szekely).