1. J. Bilbao, E. Bravo, O. Garcia, C. Varela, M. Rodriguez, P. Gonzalez, The next future of solar energy generation. Int. J. Tech. Phys. Probl. Eng. (IJTPE) Issue 12, 4(3), 162–166 (2012)
2. J. Bilbao, E. Bravo, O. Garcia, C. Varela, M. Rodriguez, P. Gonzalez, Some keys for obtaining a secure and solid energy supply in Europe. Int. J. Tech. Phys. Probl. Eng. (IJTPE) Issue 20, 6(3), 153–157 (2014)
3. European Commission, Renewable energy: moving towards a low carbon economy (2018).
https://ec.europa.eu/energy/en/topics/renewable-energy
4. The Paris Agreement. United Nations (2018).
https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement
5. Net Electric from Spain (2018).
https://www.ree.es/en