Johnston, D. (2003). International exploration economics, risk, and contract analysis. Tulsa, OK: Pennwell Corporation.
Παραπομπή Chicago StyleJohnston, Daniel. International Exploration Economics, Risk, and Contract Analysis. Tulsa, OK: Pennwell Corporation, 2003.
Παραπομπή MLAJohnston, Daniel. International Exploration Economics, Risk, and Contract Analysis. Tulsa, OK: Pennwell Corporation, 2003.
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