Somma, E., and A. Rubino. “Public-Private Participation in Energy Infrastructure in Middle East and North African Countries: The Role of Institutions for Renewable Energy Sources Diffusion”. International Journal of Energy Economics and Policy, vol. 6, no. 3, July 2016, pp. 621-9, https://www.econjournals.com/index.php/ijeep/article/view/2765.