参考文献

Wieprecht, Torsten; Schlingloff, Gunther; Xia, Juntao; Heinz, Uwe; Schneider, Abert; Dubs, Marie-Josee; Bachmann, Frank; Hazekamp, Menno; Dannacher, Josef Patent: US2006/19853 A1, 2006 ; Location in patent: Page/Page column 20 ;