参考文献

Ikeura, Yoshinori; Hashimoto, Tadatoshi; Shirai, Junya; Takeshi, Yoshikawa; Nakatani, Hiroshi; Yamano, Mitsuhisa; Mizuno, Masahiro; Irie, Hiroyuki Patent: US2006/241145 A1, 2006 ; Location in patent: Page/Page column 45; 46 ; US 20060241145 A1