APA (7th ed.) Citation

United States. Bureau of Chemistry and Soils, University of Puerto Rico (Río Piedras Campus). Agricultural Experiment Station, & Roberts, R. C. (1936). Soil map, Puerto Rico (Printers proof, subject to correction.). Bureau of Chemistry and Soils, Field Operations.

Chicago Style (17th ed.) Citation

United States. Bureau of Chemistry and Soils, University of Puerto Rico (Río Piedras Campus). Agricultural Experiment Station, and Ray Carlton Roberts. Soil Map, Puerto Rico. Printers proof, subject to correction. [Washington, D.C.?]: Bureau of Chemistry and Soils, Field Operations, 1936.

MLA (9th ed.) Citation

United States. Bureau of Chemistry and Soils, et al. Soil Map, Puerto Rico. Printers proof, subject to correction. Bureau of Chemistry and Soils, Field Operations, 1936.