参考文献

Kim, Jung-Keun; Kim, Se-Won; Oh, Kwi-Ok; Ko, Seon Yle; Kim, Jong Yeo; Lee, Byung-Eui; Kim, Bum Tae; Lee, Yeon Soo; Min, Yong Ki; Park, No Kyun Patent: US2008/221205 A1, 2008 ; Location in patent: Page/Page column 5-6 ;