JOURNAL OF THE KOREAN PHYSICAL SOCIETY, vol. 53, no. 6, page. 3827 - 3831, 2008-12
OPTICS LETTERS, vol. 33, no. 20, page. 2392 - 2394, 2008-10-15
APPLIED OPTICS, vol. 47, no. 16, page. 3064 - 3071, 2008-06-01