TY  - BOOK
AU  - Proctor,Robert V.
AU  - White,Thomas L.
AU  - Terzaghi,Karl
TI  - Rock tunneling with steel supports / 
PY  - 1946///
CY  - Ohio: 
PB  - [Commercial Shearing & Stamping Co.]
KW  - TUNELES
KW  - ROCAS
KW  - EXCAVACIONES
UR  - https://archive.org/details/rock-tunneling-with-steel-supports-introduction-to-tunnel-geology-by-r.-v.-proct/page/168/mode/2up
ER  -