W Economic sectors > W.06 Manufacturing industries > W.06.06 Oil industry > Oil and gas services

W Economic sectors > W.06 Manufacturing industries > W.06.06 Oil industry > Oil industry > Oil and gas services

... > V Economics > V.12 Environmental and resource economics > V.12.02 Energy economics > Energy sector > Oil industry > Oil and gas services

... > W Economic sectors > W.22 Public sector > Public utilities > Energy sector > Oil industry > Oil and gas services

... > W Economic sectors > W.04 Energy and Water Industries > W.04.01 Energy sector > Energy sector > Oil industry > Oil and gas services

W Economic sectors > W.05 Resource Sector and Mining > W.05.01 Mining > W.05.01.02 Crude Petroleum and Natural Gas Production > Oil and gas services