TY - RPRT TI - Standard Reference Materials : Metal-on-quartz filters as a standard reference material for spectrophotometry - SRM 2031/ AU - Baldwin, J R AU - Mavrodineanu, R PY - 1980 PB - National Institute of Standards and Technology CY - Gaithersburg, MD SN - NBS SP 260-68 DO - 10.6028/NBS.SP.260-68 ER -