http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
General fertilizer recommendations for the West Cross Timbers, East Cross Timbers, North Central Prairie, and Central Basin
Developed by personnel of the Department of Soil and Crop Sciences, College Station, and Substation No. 20, Stephenville, of Texas A&M University.
The United States Department of Agriculture cooperating.
Leaflet (Texas Agricultural Extension Service) ; 221 [1963 revised]