Não informado. (1972). Environmental Geology Report. Bureau of Topographic and Geologic Survey.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Environmental Geology Report. Harrisburg, Pa: Bureau of Topographic and Geologic Survey, 1972.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Environmental Geology Report. Bureau of Topographic and Geologic Survey, 1972.
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