TY - RPRT TI - National voluntary laboratory accreditation program: chemical calibration certifiers of spectrophotometric NTRMs AU - Kramer, Gary W AU - Travis, John C AU - Faison, C Douglas AU - Rasberry, Stanley D PY - 2000 PB - National Institute of Standards and Technology CY - Gaithersburg, MD SN - NIST HB 150-21 DO - 10.6028/NIST.HB.150-21 ER -