参考文献

Blake, Tanisha D.; Hamper, Bruce C.; Huang, Wei; Kiefer, James R.; Moon, Joseph B.; Neal, Bradley E.; Olson, Kirk L.; Pelc, Matthew J.; Schweitzer, Barbara A.; Thorarensen, Atli; Trujillo, John I.; Turner, Steven R. Patent: US2008/146569 A1, 2008 ; Location in patent: Page/Page column 19 ; US 20080146569 A1