APA (7th ed.) Citation

Smith, R. L., & Geological Survey. (1960). Zones and zonal variations in welded ash flows. United States Department of the Interior, Geological Survey.

Chicago Style (17th ed.) Citation

Smith, Robert L., and Geological Survey. Zones and Zonal Variations in Welded Ash Flows. Washington: United States Department of the Interior, Geological Survey, 1960.

MLA (8th ed.) Citation

Smith, Robert L., and Geological Survey. Zones and Zonal Variations in Welded Ash Flows. United States Department of the Interior, Geological Survey, 1960.