Não informado. (2022). Progress Report. Commonwealth of Pennsylvania, Department of Internal Affairs, Bureau of Topographic and Geologic Survey.
Chicago-referens (17:e uppl.)Não informado. Progress Report. Harrisburg, Pa: Commonwealth of Pennsylvania, Department of Internal Affairs, Bureau of Topographic and Geologic Survey, 2022.
MLA-referens (8:e uppl.)Não informado. Progress Report. Commonwealth of Pennsylvania, Department of Internal Affairs, Bureau of Topographic and Geologic Survey, 2022.
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