Chi, Dae-Yoon; Lee, Byoung-Se; Uthaiwan, Sirion; Chu, So-Young; Bae, Yu-Jin; Park, Chansoo; Moon, Dae-Hyuk; Ryu, Jin-Sook; Kim, Jae-Seung; Oh, Seung-Jun Patent: US2012/214994 A1, 2012 ; Location in patent: Page/Page column 14 ;