TY  - RPRT
TI  - Circular of the Bureau of Standards no. 437: optical and mechanical characteristics of 16-millimeter motion-picture projectors
AU  - Stephens, Robert E
PY  - 1942
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS CIRC 437
DO  - 10.6028/NBS.CIRC.437
ER  -