United States. National Park Service
Agate Fossil Beds National Monument, Nebraska
United States. National Park Service · 2018
ספרייה ציבורית, Project Gutenberg. בלי הרשמה.
Paleontology -- MioceneVertebrates, Fossil -- Nebraska -- Agate Fossil Beds National MonumentPaleontology -- Nebraska -- Agate Fossil Beds National MonumentNatural history -- Nebraska -- Agate Fossil Beds National MonumentAgate Fossil Beds National Monument (Neb.)
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