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ChevronTexaco
Clements Exploration
Inc.
Corelab
East African Oil
Company Ltd.
ECL
Exile Resources Ltd.
ExxonMobil
Fina
First Exchange Inc.
Fortesa Inc.
Fugro Geoscience Division
Gaffney Cline
Geolab
Geotrex Systems
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Pty Ltd.
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Zeta Petroleum