Leontiy Ivanovich Sivtsov (Russian: Леонтий Иванович Сивцов; 1872–1919) was a church reader who lived in Unalaska. Along with Aleksey Yachmenev, who like Sivtsov was Aleut himself, Sivtsov accompanied Waldemar Jochelson on his 1909–1910 ethnological studies on the Aleut.

• Bergsland, Knut (1994). Aleut Dictionary = Unangam Tunudgusii: an unabridged lexicon of the Aleutian, Pribilof, and Commander Islands Aleut language. Fairbanks, AK: Alaska Native Language Center, University of Alaska. ISBN 1-55500-047-9. P. viii