TY  - RPRT
TI  - Letter Circular 624: list of commercial standards (supersedes Letter Circular 609)
PY  - 1941
PB  - National Institute of Standards and Technology
CY  - Gaithersburg, MD
SN  - LCIRC 624r1941
DO  - 10.6028/NBS.LCIRC.624r1941
ER  -