À propos de cet article
Publié en ligne: 03 oct. 2013
Pages: 323 - 327
DOI: https://doi.org/10.2478/jos-2013-0025
This content is open access.
Joseph S Kosler
United States Department of Agriculture National Agricultural Statistics Service (NASS) Research and Development Division 3251 Old Lee Highway Fairfax, VA 22030