参考文献

Kung, Liang-Rern; Chang, Shih-Sheng; Fang, Tung-Shen; Lin, Shu-Fen; Chang, Cheng-Chang; Chen, Chia-Hui; Hung, Yi-Ting; Cheng, Ming-Ching Patent: US2012/149925 A1, 2012 ; Location in patent: Page/Page column 9 ;