Columbia subject headings:
Ti︠u︡tchev, F. I. (Fedor Ivanovich), 1803-1873.
Harvard subject headings:
Ti͡utchev, F. I. (Fedor Ivanovich), 1803-1873.
Princeton subject headings:
Ti︠u︡tchev, F. I. (Fedor Ivanovich), 1803-1873.