TY - RPRT TI - Results of the U.S. Geological Survey's analytical evaluation program for standard reference samples distributed in March 2003 AU - Mark T. Woodworth AU - Brooke F. Connor PY - 2003 DO - 10.3133/ofr03261 UR - https://pubs.usgs.gov/publication/ofr03261 ID - ofr03261 ER -