参考文献

Nishi, Kiyohiko; Kaneko, Hiroshi; Tasaki, Hirofumi; Koga, Masaki; Tanegawa, Tetsuo; Furuya, Seisaku; Fujiwara, Kenji; Sato, Takeru Patent: US2010/94051 A1, 2010 ; Location in patent: Page/Page column 5 ;