TY  - RPRT
TI  - Development of draft construction safety standards for excavations : an NBSNIOSH publication : volume I
AU  - Yokel, Felix Y
PY  - 1983
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS IR 83-2693v1
DO  - 10.6028/NBS.IR.83-2693v1
ER  -