TY  - RPRT
TI  - Letter Circular 809: color charts: a descriptive list (superseding Letter Circular 665)
PY  - 1945
PB  - National Institute of Standards and Technology
CY  - Gaithersburg, MD
SN  - LCIRC 809
DO  - 10.6028/NBS.LCIRC.809
ER  -