http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Improvement of sheep through the selection of performance-tested and progeny-tested breeding animals, 1950-51
Conducted at the Ranch Experiment Station, Sonora, W.T. Hardy, Superintendent.
The United States Department of Agriculture cooperating.
Miscellaneous publication (College Station, Tex.) ; no. 75