TY - JOUR AU - James Butler AU - B. Johnson AU - R Barnes C2 - The Earth Observer DA - 2002-07-01 00:07:00 LA - en M1 - 14 PB - The Earth Observer PY - 2002 TI - Radiometric Measurement Comparisons at NASA's Goddard Space Flight Center: Part II. Irradiance Lamp Comparisons and the NIST Sphere Source ER -