Não informado. (2022). Progress Report. Commonwealth of Pennsylvania, Department of Internal Affairs, Bureau of Topographic and Geologic Survey.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Progress Report. Harrisburg, Pa: Commonwealth of Pennsylvania, Department of Internal Affairs, Bureau of Topographic and Geologic Survey, 2022.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Progress Report. Commonwealth of Pennsylvania, Department of Internal Affairs, Bureau of Topographic and Geologic Survey, 2022.
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