Cita APA

National Soil Survey Center (Estados Unidos), Estados Unidos Natural Resources Conservation Service, & Estados Unidos Department of Agriculture. (2012). Field book for describing and sampling soils: Version 3.0. [Estados Unidos]: USDA-NRCS.

Citación estilo Chicago

National Soil Survey Center (Estados Unidos), Estados Unidos Natural Resources Conservation Service, y Estados Unidos Department of Agriculture. Field Book for Describing and Sampling Soils: Version 3.0. [Estados Unidos]: USDA-NRCS, 2012.

Cita MLA

National Soil Survey Center (Estados Unidos), Estados Unidos Natural Resources Conservation Service, y Estados Unidos Department of Agriculture. Field Book for Describing and Sampling Soils: Version 3.0. [Estados Unidos]: USDA-NRCS, 2012.