Introduction to petroleum geology / by G.D. Hobson and E.N. Tiratsoo. Petroleum geology. Hobson, George Douglas. Tiratsoo, E. N. (Eric Neshan), 1915- Petroleum Geology. 19 553.282 HOI Includes bibliographies and index. Houston, Tex. : Gulf Pub. Co., 1981. 1981. 1981 Text viii, 352 p. : eng