TY - GEN AU - Eckerle, Kenneth L C2 - , National Institute of Standards and Technology, Gaithersburg, MD DA - 1976-01-01 05:01:00 DO - https://doi.org/10.6028/NBS.TN.913 LA - en PB - , National Institute of Standards and Technology, Gaithersburg, MD PY - 1976 TI - Modification of an NBS reference spectrophotometer: ER -