000
00251nam a2200109Ia 4500
008
220201s1971 xx 000 0 eng d
100
_a
Saxena,Subhash C.
245
0
_a
Tunnel Engineering
260
_b
Dhanpat rai
_c
1971
300
_a
175
942
_2
ddc
999
_c
79750
_d
79750