参考文献

Mueller, Stephan Georg; Rudolf, Klaus; Lustenberger, Philipp; Stenkamp, Dirk; Santagostino, Marco; Paleari, Fabio; Doods, Henri; Arndt, Kirsten; Schaenzle, Gerhard Patent: US2007/72847 A1, 2007 ; Location in patent: Page/Page column 75 ; US 20070072847 A1