1. Stratigraphic notes, 1992 : four short papers propose changes in stratigraphic nomenclature in Vermont, Virginia, Maryland, and the District of Columbia Publication/Creation: Denver, CO : For sale by U.S. Geological Survey, Information Services Resource Type: Book Access & Availability: Loading
2. Stratigraphic notes, 1993 : two short papers propose changes in stratigraphic nomenclature in Maryland and Virginia Author/Creator: Drake, Avery Ala, 1927- Publication/Creation: Denver, CO : For sale by U.S. Geological Survey, Map Distribution Resource Type: Book Access & Availability: Loading