APA (7th ed.) Citation

Cathcart, J. B., Mojica G., P. E., & Zambrano O., F. (1969). Phosphate rock in Colombia: A preliminary report. United States Department of the Interior, Geological Survey.

Chicago Style (17th ed.) Citation

Cathcart, James Bachelder, Pedro E. Mojica G., and Francisco Zambrano O. Phosphate Rock in Colombia: A Preliminary Report. [Washington, D.C.]: United States Department of the Interior, Geological Survey, 1969.

MLA (9th ed.) Citation

Cathcart, James Bachelder, et al. Phosphate Rock in Colombia: A Preliminary Report. United States Department of the Interior, Geological Survey, 1969.