Analysis of information sources in references of the Wikipedia article "North Slavic languages" in English language version.
The present-day Slavic peoples are usually divided into the three following groups: West Slavic, East Slavic, and South Slavic. This division has both linguistic and historico-geographical justification, in the sense that on the one hand the respective Slavic languages show some old features which unite them into the above three groups, and on the other hand the pre- and early historical migrations of the respective Slavic peoples distributed them geographically in just this way.
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