1. S. Habibulla, Non-conventional energy sources for the course of rural engineering technician (State Institute of Vocational Education, Directorate of Intermediate Education, Govt. of Andhra Pradesh, Hyderabad, India. 2005).
2. K.S. Sidhu, Non-conventional energy sources, Link: www.indiacore.com/bulletin/kssidhu-non-conventional-energy-resources.
3. S. K. Singal and Varun, Development of non-conventional energy sources, 9th NCB International Seminar on Cement and Building Materials, New Delhi, Nov. 8-11, (2005).
4. “Application of non-conventional & renewable energy sources,” Link: https://beeindia.gov.in/sites/default/files/4Ch12.pdf.
5. Sources: Agencia Internacional de la Energía, (2015), Ten reasons to support renewable energy - Sustainability for all.