Analysis of information sources in references of the Wikipedia article "Kozachok" in English language version.
According to the 1897 census, 49.1 per cent of the population considered their native language to be Ukrainian, and 41.8 per cent considered it to be Russian (not including Black Sea gubernia). Over one-third of the inhabitants were born outside Kuban. Of these, 24.2 per cent were born in the ethnically mixed Voronezh and Kursk gubernias and 40.1 per cent were born in the Ukrainian Kharkiv gubernia, Poltava gubernia, Katerynoslav gubernia, and Chernihiv gubernia; the number of immigrants from Kyiv gubernia and Kherson gubernia was also significant. By 1926, the total population of Kuban was 3,557,000 (including Black Sea gubernia). Of these, 47.1 percent (1,674,000) were Ukrainians, 41 percent (1,460,000) Russians, 4.9 percent (172,000) various Caucasian mountain peoples