APA (7th ed.) Citation

Geological Survey (U.S.). (1980). Duluth, Minnesota--Wisconsin: 1:100 000-scale metric topographic map. The Survey.

Chicago Style (17th ed.) Citation

Geological Survey (U.S.). Duluth, Minnesota--Wisconsin: 1:100 000-scale Metric Topographic Map. Reston, Va.: The Survey, 1980.

MLA (9th ed.) Citation

Geological Survey (U.S.). Duluth, Minnesota--Wisconsin: 1:100 000-scale Metric Topographic Map. The Survey, 1980.

Warning: These citations may not always be 100% accurate.