Wengler, J. (2001). Managing energy risk: A nontechnical guide to markets and trading. Tulsa, OK: Pennwell Publishing Company.
Παραπομπή Chicago StyleWengler, John. Managing Energy Risk: A Nontechnical Guide to Markets and Trading. Tulsa, OK: Pennwell Publishing Company, 2001.
Παραπομπή MLAWengler, John. Managing Energy Risk: A Nontechnical Guide to Markets and Trading. Tulsa, OK: Pennwell Publishing Company, 2001.
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