Online Public Access Catalogue (OPAC)Library,Documentation and Information Science Division
“A research journal serves that narrow
borderland which separates the known from the unknown”
-P.C.Mahalanobis
551.22 Ob12 PH1326
Obert Leonard Micro-seismic method of determining the stability of underground openings 1957 18p. photo-print from US Bureau of Mines, Bull. 573, 1957. * Geology Seismology * Duvall W I, Auth. * Title