Image from the Biodiversity Heritage Library.
Contributed by Yale Peabody Museum of Natural History.
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Transcription
Butt, Ch., 1933. Geol. Map of
the Appalachian Valley
of Va. with Explanatory
Text. Va. Geol. Surv. Bull. 42.
Butt, Ch., Stoe, G.W. & Tonus, A.I.,
1932. Int. Geol. Congress.
16th Session U. States,
1933, Guidebook 3; Excursion
A-3. Southern Appalachian
Region