1. (1) N. Morita: “The role of JSPS in the history of carbon brushes for motors and generators and its role in today's era of globalization”, Japan Society for the Promotion of Science 117 Committee, 117-D-131-3 (2017)
2. (2) N. Morita: “Dictionary of carbon”, Asakura Publishing Co., Ltd., pp. 509-518 (2017)
3. (3) J. Twidell and G. Gaudiosi: “Offshore wind power”, KAJIMA INSTITUTE PUBLISHING CO., LTD., pp. 77-79 (2011)
4. (4) Y. Nishitani: “Radio equipment”, SEIZANDO-SHOTEN PUBLISHING CO.,LTD., pp. 53-56 (1991)
5. (5) H. Yamagata: “Medical equipment II”, CORONA PUBLISHING CO., LTD., pp. 18-47 (2006)