1. Taylor LD (1975) Bell J Econ JSTOR
2. Lutz W, Sanderson WC, Scherbov S (2004) Google book
3. World Energy Outlook (2013) Universal access to modern energy for poor
4. Tanzer M Energy crisis: world struggle for power and wealth
5. Midilli A, Dincer I (2005) Murat Ay-2005-energy policy