Youngquist, Walter. Annotated Lexicon of Names Applied to Tertiary Stratigraphic Units in Oregon and Washington West of the Cascade Mountains, with Bibliography. Ann Arbor, Michigan: Edwards Brothers, Inc., 1961.

Youngquist, Walter. Annotated Lexicon of Names Applied to Tertiary Stratigraphic Units in Oregon and Washington West of the Cascade Mountains, with Bibliography. Ann Arbor, Michigan: Edwards Brothers, Inc., 1961.