TY - RPRT TI - Spectrophotometric and colorimetric study of color transparencies of some man-made objects AU - Keegan, Harry J AU - Haas, Galdys M AU - Hall, Wiley A, Jr PY - 1957 PB - National Bureau of Standards CY - Gaithersburg, MD SN - NBS RPT 4953 DO - 10.6028/NBS.RPT.4953 ER -