ADDAX Petroleum (Switzerland)
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BEB Erdgas und Erdöl GmbH (Germany)
BGP (China)
BGR Federal Institute for Geosciences and Natural
BP (United Kingdom)
Resources (Germany)
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Cairn Energy PLC (United Kingdom)
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Centrica Energy (United Kingdom)
Chevron Texaco (United Kingdom)
COWI A/S (Denmark)
Dansk Naturgas A/S (Denmark)
DEUSA GmbH (Germany)
Deilmann Erdöl Erdgas GmbH (Germany)
DMT (Germany)
DONG A/S (Denmark)
EEG GmbH (Germany)
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EnCana (Canada)
Exxon Mobil Production Germany (Germany)
Faroe Petroleum (United Kingdom)
Gedco (Canada)
Geonafta ( Lithuania)
Geowindow Co. Ltd. (Japan)
GNPOC (Sudan)
Heritage Oil Ltd. (United Kingdom)
Hess Ltd. (United Kingdom)
KBB GmbH (Germany)
Linde Gas (Germany)
Maersk Olie og Gas (Denmark)
Max Petroleum (Kazakhstan)
Medusa Oil & Gas SP. z o.o (Poland)
Mobil Erdgas-Erdöl GmbH (Germany)
NIOC (Iran)
North Sea Oil Company (USA)
Nafta a.s. Gbely (Slovakia)
NAM B.V. (The Netherlands)
Occidental Oil and Gas Corporation(USA)
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OMV Albania ( Albania)
PDO (Petroleum Development Oman)
PDOC Petrodar Operating Co. (Sudan)
Pemex (Mexico)
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Petronas ( Malaysia )
POL (Pakistan OilFields Limited)
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Premier Kufpec Pakistan B.V. (Pakistan)
Preussag Energie GmbH (Germany)
Qatar Petroleum
RAG Rohöl-Aufsuchungs AG (Austria)
Ramboll (Denmark)
Repsol YPF (Spain)
Ruhrgas AG (Germany)
RWE DEA AG (Germany)
RWE DEA Netherlands B. V. (The Netherlands)
RWE DEA Polska SP. z o.o (Poland)
Samek International (Kazakhstan)
Sasoil West Africa Limited (USA)
Sipetrol (United Kingdom)
Sinopec Shengli (China)
SPP a.s. Bratislava (Slovakia)
Statoil ASA (Norway)
Sterling Energy PLC (UK)
Sydkraft AB (Sweden)
TEIKOKU (Japan)
Tullow Oil (Ireland)
VEBA Oel GmbH (Germany)
VITO, Flemish institute for technological research (Belgium)
VNG Verbundnetz Gas AG (Germany)
Wintershall AG (Germany)
Wintershall Libya (Libya)
Wintershall Noordzee B. V. (The Netherlands)
Wintershall Norge (Norway)
Woodside Petroleum Ltd. (Australia)
Zhibek Resources PLC (Kyrgyzstan)

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