TY - GEN AU - Yoshihiro Ohno C2 - , National Institute of Standards and Technology, Gaithersburg, MD DA - 1997-01-01 05:01:00 DO - https://doi.org/10.6028/NIST.SP.250-37 LA - en PB - , National Institute of Standards and Technology, Gaithersburg, MD PY - 1997 TI - Photometric calibrations: ER -