Não informado. (1999). Special report. Wisconsin Geological and Natural History Survey.
Chicagoスタイル(17版)引用形式Não informado. Special Report. Madison, Wis: Wisconsin Geological and Natural History Survey, 1999.
MLA(8版)引用形式Não informado. Special Report. Wisconsin Geological and Natural History Survey, 1999.
警告: この引用は必ずしも正確ではありません.