Long, D. (2003). Gas Trading Manual (Second Edition). ELSEVIER.
Cita Chicago (17th ed.)Long, David. Gas Trading Manual (Second Edition). ELSEVIER, 2003.
Cita MLA (8th ed.)Long, David. Gas Trading Manual (Second Edition). ELSEVIER, 2003.
Atenció: Aquestes cites poden no estar 100% correctes.