Kuzmin, Yaroslav V., Speakman, Robert Jeff, Glascock, Michael D., Popov, Vladimir K., Grebennikov, Andrei V., Dikova, Margarita A., and Ptashinsky, Andrei V. 2008. "
Obsidian use at the Ushki Lake complex, Kamchatka Peninsula (Northern Siberia): Implications for Terminal Pleistocene and Early Holocene Human Migrations in Beringia."
Journal of Archaeological Science, 35, (8) 2179–2187.
https://doi.org/10.1016/j.jas.2008.02.001.