TY  - RPRT
TI  - Letter Circular 1004: light-sensitive paper no. 1554, directions for use in testing textiles for colorfastness to light (superseding Letter Circular 934)
PY  - 1951
PB  - National Institute of Standards and Technology
CY  - Gaithersburg, MD
SN  - LCIRC 1004
DO  - 10.6028/NBS.LCIRC.1004
ER  -