APA (7th ed.) Citation

Geological Survey (U.S.) & Geological Survey (U.S.). National Mapping Division. (1994). Index to USGS/DMA 1:50,000-scale, 15-minute mapping: (contours and elevations in meters). Geological Survey.

Chicago Style (17th ed.) Citation

Geological Survey (U.S.) and Geological Survey (U.S.). National Mapping Division. Index to USGS/DMA 1:50,000-scale, 15-minute Mapping: (contours and Elevations in Meters). Reston, Va.: Geological Survey, 1994.

MLA (9th ed.) Citation

Geological Survey (U.S.) and Geological Survey (U.S.). National Mapping Division. Index to USGS/DMA 1:50,000-scale, 15-minute Mapping: (contours and Elevations in Meters). Geological Survey, 1994.