TY  - RPRT
TI  - Survey of roofing materials in the north central states 
AU  - Snoke, Hubert R
AU  - Waldron, Leo J
PY  - 1941
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS BMS 75
DO  - 10.6028/NBS.BMS.75
ER  -