Cita APA (7th ed.)
Leffler, W. L., & Womack, K. (2014). Natural gas liquids: A nontechnical guide. PennWell Corporation.
Cita Chicago (17th ed.)
Leffler, William L., i Karla Womack. Natural Gas Liquids: A Nontechnical Guide. Tulsa, Oklahoma: PennWell Corporation, 2014.
Cita MLA (9th ed.)
Leffler, William L., i Karla Womack. Natural Gas Liquids: A Nontechnical Guide. PennWell Corporation, 2014.
Atenció: Aquestes cites poden no estar 100% correctes.