International Energy Agency. (2017). Spot market and crude oil import costs: Crude oil spot prices (Edition 2017). OECD Publishing. https://doi.org/10.1787/9f507630-en
Chicago-Zitierstil (17. Ausg.)International Energy Agency. Spot Market and Crude Oil Import Costs: Crude Oil Spot Prices (Edition 2017). Paris: OECD Publishing, 2017. https://doi.org/10.1787/9f507630-en.
MLA-Zitierstil (9. Ausg.)International Energy Agency. Spot Market and Crude Oil Import Costs: Crude Oil Spot Prices (Edition 2017). OECD Publishing, 2017. https://doi.org/10.1787/9f507630-en.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.