TY  - RPRT
TI  - Study of the national standards for directional and other official signs : overview of their adequacy
AU  - Fechter, John V
AU  - Pezoldt, Valom J
AU  - Persensky, J J
AU  - Lepkowski, J Richard
PY  - 1975
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS IR 75-777
DO  - 10.6028/NBS.IR.75-777
ER  -