TY  - BOOK
AU  - Raju,N.M.
AU  - Singh,B.
ED  - Central Mining Research Station
TI  - Roof bolting anchorage efficiency of 22 mm diameter wedge and slot type roof bolts in a group of collieries
U1  - 622.(54) 
PY  - 1967///
CY  - Dhanbad
PB  - Central Mining Research Station
ER  -