TY  - RPRT
TI  - Circular of the Bureau of Standards no. 178: United States government master specification for the construction of built-up roofing, type 4TWS
PY  - 1924
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS CIRC 178
DO  - 10.6028/NBS.CIRC.178
ER  -