参考文献

Ehlert, Jan; Herz, Thomas; Krauss, Rolf; Kubbutat, Micheal; Lang, Martin; Pegoraro, Stefano; Schachtele, Christoph; Totzke, Frank; Zirrgiebel, Ute Patent: US2007/149523 A1, 2007 ; Location in patent: Page/Page column 13 ;