Não informado. (1954). Virginia minerals. Department of Conservation and Development, Division of Geology.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Virginia Minerals. Charlottesville, Va: Department of Conservation and Development, Division of Geology, 1954.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Virginia Minerals. Department of Conservation and Development, Division of Geology, 1954.
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