APA

United States Geological Survey, USA, . (19331948). Circular / US Department of the Interior, Geological Survey. Washington, DC: US Gov.Print.Off.

Chicago

United States Geological Survey, USA, . 19331948. Circular / US Department of the Interior, Geological Survey. Washington, DC: US Gov.Print.Off.

Harvard

United States Geological Survey, USA, . (19331948). Circular / US Department of the Interior, Geological Survey. Washington, DC: US Gov.Print.Off.

MLA

United States Geological Survey, USA, . Circular / US Department of the Interior, Geological Survey. Washington, DC: US Gov.Print.Off. 19331948.