1. Kenji Ishikawa, Potential and Limitation of Natural energy, 2009, pp.100-102.
2. Daisuke Imaizumi, Best Understood Renewable Energy, 2013, pp.92-103.
3. Y. Koyamatsu, A. Shiota, and Y. Mitani, Simulation of Solar Radiation on installation surface of PV Panels Using Geographic Information System, IEEJ Kyushu Branch, 2015.
4. Japan Photovoltaic Energy Association (2015), The current state of solar power and introduction prospect, [Online] Available http://www.jpea.gr.jp/pdf/150330.
5. Tsutomu Ohyama, Masakazu Kato, and Hiroshi Asano, Future of Electric Smart Grid, 2011, pp.94-98.