Não informado. (2001). Bulletin of the Wisconsin Geological and Natural History Survey. Wisconsin Geological and Natural History Survey.
Chicago-viite (17. p.)Não informado. Bulletin of the Wisconsin Geological and Natural History Survey. Madison, Wis: Wisconsin Geological and Natural History Survey, 2001.
MLA-viite (8. p.)Não informado. Bulletin of the Wisconsin Geological and Natural History Survey. Wisconsin Geological and Natural History Survey, 2001.
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