TY  - BOOK
AU  - Wittke, W..
TI  - Rock mechanics:caverns pressure shafts / 
SN  - 90 6191 233 4
U1  - HZ,2(B7) 
PY  - 1979///
CY  - Rotterdam : 
PB  - A.A.Balkema , 
KW  - Earth Science
ER  -