Identification and nomenclature of soil horizons :
supplement to Agricultural handbook no. 18, Soil Survey manual /
U.S. Department of Agriculture, Soil Conservation Service.

APA Citation

United States. Soil Conservation Service. (1962). Identification and nomenclature of soil horizons: supplement to Agricultural handbook no. 18, Soil Survey manual. [Washington]: U.S. Govt. Print. Off..

MLA Citation

United States. Soil Conservation Service. Identification And Nomenclature of Soil Horizons: Supplement to Agricultural Handbook No. 18, Soil Survey Manual. [Washington]: U.S. Govt. Print. Off., 1962.

Warning: These citations may not always be complete (especially for serials).