[1] Changing ideas on the identity and stratigraphic significance of the Sheep Creek tephra beds in Alaska and the Yukon Territory, northwestern North America, 2008

Westgate, J.A., Preece, S.J., Froese, D.G., Pearce, N.J.G., Roberts, R.G., Demuro, M., Hart, W.K., and Perkins, W., 2008, Changing ideas on the identity and stratigraphic significance of the Sheep Creek tephra beds in Alaska and the Yukon Territory, northwestern North America: Quaternary International, v. 178, n. 1, p. 183-209, doi: 10.1016/j.quaint.2007.03.009.

[2] Late Pliocene Dawson Cut forest bed and new tephrochronological findings in the Gold Hill Loess, east-central Alaska, 2009

Pewe, T.L., Westgate, J.A., Preece, S.J., Brown, P.M., and Leavitt, S.W., 2009, Late Pliocene Dawson Cut forest bed and new tephrochronological findings in the Gold Hill Loess, east-central Alaska: Geological Society of America Bulletin, v. 121, n. 1-2, p. 294-320, doi: 10.1130/B26323.1 .