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(named after the French town of Cognac), third stage from the bottom of the Upper Cretaceous. It was established in 1857 by the French geologist H. Coquand. It is identified throughout the countries of Western Europe (France, Great Britain, the Federal Republic of Germany, the German Democratic Republic, the Polish People’s Republic) and in the USSR (Volga Region, Crimea, the Caucasus, Bol’shoi Balkhan, the northeastern part of the country) by the presence of a characteristic complex of foraminifers, inocerams (Inoceramus involutus Sow.), and other fossils.