Cita APA (7th ed.)

Spurr, J. E. (1920). Political and commercial geology and the world's mineral resources: A series of studies by specialists. McGraw-Hill.

Cita Chicago (17th ed.)

Spurr, Josiah Edward. Political and Commercial Geology and the World's Mineral Resources: A Series of Studies by Specialists. New York: McGraw-Hill, 1920.

Cita MLA (8th ed.)

Spurr, Josiah Edward. Political and Commercial Geology and the World's Mineral Resources: A Series of Studies by Specialists. McGraw-Hill, 1920.