1. Energy saving and environmental measures in railway technologies;Ogasa;IEEJ Transactions,2008
2. Development and running test results of a contact-wire-less tramcar using lithium ion rechargeable battery;Ogasa;IEEJ Research Paper on Transportation and Electric Railway,2004
3. Alstom. APS wire-free system. http://www.transport.alstom.com/home/elibrary/technical/environnement/_files/file_31288_29589.pdf, 2004.
4. Bombardier. First catenary-free and contact-less operating tram. http://www.bombardier.com/en/corporate/media-centre/press-releases/, 2009.
5. Energy storage in board of DC fed railway vehicles;Steiner;PESC Conference Proceedings,2004