参考文献

Dandala, Ramesh; Mallela, Sambhu Prasad Sarma; Nandi, Sukumar; Nangi, Gangadhar Bhima Shankar; Buridipadu, Sunil Kumar; Meenakshisunderam, Sivakumaran Patent: US2010/29940 A1, 2010 ; Location in patent: Page/Page column 9 ;