参考文献:
Lynch, John K. Collins, Christine A. Freeman, Jennifer C. Gao, Ju Iyengar, Rajesh R. Judd, Andrew S. Kym, Philip R. Mulhern, Mathew M. Sham, Hing L. Souers, Andrew J. Zhao, Gang Wodka, Dariusz Patent: US25/2927 A, 25 Location in patent: Page/Page column 35-36 US 252927 A