TY  - RPRT
TI  - Bureau circular no. 15, April 1, 1909 edition: a proposed international unit of light
PY  - 1909
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS CIRC 15-April1909
DO  - 10.6028/NBS.CIRC.15-April1909
ER  -