参考文献:
Walker, Daniel Patrick Piotrowski, David W. Jacobsen, Eric Jon Acker, Brad A. Groppi JR., Vincent E. Patent: US2003/232853 A1, 2003 Location in patent: Page 44
参考文献:
Wishka, Donn G. Walker, Daniel Patrick Corbett, Jeffrey W. Reitz, Steven Charles Rauckhorst, Mark R. Groppi JR., Vincent E. Patent: US2003/105089 A1, 2003 US 20030105089 A1