EDIT 25th letter in Russian and Belorusian alphabets and upper case letter corresponding to the lower case ч (U+0447)

Transliterates according to international ISO (and German DIN) standard as /Č/ (U+010C), e.g. П. Я. Чаадаев (Russian philosopher, 1794-1856, exiled for his criticism of Russias role in world history and politics) - Čaadaev
English (BSI, ALA) standard transliteration: /Ch/ - Chaadaev

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