TY  - RPRT
TI  - Circular of the Bureau of Standards no. 13 9th edition: standard specifications for incandescent electric lamps (tungsten and carbon)
PY  - 1921
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS CIRC 13e9
DO  - 10.6028/NBS.CIRC.13e9
ER  -