参考文献

Adam, Jean-Michel; Aebi, Johannes; Binggeli, Alferd; Green, Luke; Hartmann, Guido; Maerki, Hans P.; Mattei, Patrizio; Ricklin, Fabienne; Roche, Olivier Patent: US2009/318467 A1, 2009 ; Location in patent: Page/Page column 23 ;