1. U.S. Energy Information Administration. International Energy Outlook 2016: with projections to 2040
2. May 2016. www.eia.gov/forecasts/ieo/pdf/0484(2016).pdf.
3. BP Statistical Review of World Energy June 2017. http://www.bp.com/content/dam/bp/en/corporate/pdf/energy-economics/statistical-review-2017/bp-statistical-review-of-world-energy-2017-full-report.pdf.
4. Literature Review;Islam,2017
5. Current alternative engine fuels;Balat;Energy Sources,2005