TY  - RPRT
TI  - Circular of the Bureau of Standards no. 428: a test of lens resolution for the photographer
AU  - Gardner, Irvine C
PY  - 1940
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS CIRC 428
DO  - 10.6028/NBS.CIRC.428
ER  -