TY  - RPRT
TI  - Circular of the Bureau of Standards no. 505: preservation of the declaration of independence and the Constitution of the United States
PY  - 1951
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS CIRC 505
DO  - 10.6028/NBS.CIRC.505
ER  -