O'connell Richard J.
O'doherty Ronan F.
O'keefe Graeme Joseph
O'reilly Donald E.
O'sullivan Terence P.
O. Y. O. Corporation
Obata Sukiro
Obi Aghogho
Object Reservoir Inc.
Ocean Floor Geophysics Inc.
Ockleston Grant Andrew
Odegaard & Danneskiold-Samsoe Aps
Odom Richard Charles
Oezbek Ali
Oezdemir Ahmet Kemal
Offshore Hydrocarbon Mapping Plc
Ogura Kazumasa
Ohm Limited
Ohmer Herve
Okamura Shinichiro