JOURNAL OF THE KOREAN PHYSICAL SOCIETY, vol. 64, no. 7, page. 976 - 981, 2014-04
JOURNAL OF THE KOREAN PHYSICAL SOCIETY, vol. 58, no. 2, page. 198 - 204, 2011-02
JOURNAL OF THE KOREAN PHYSICAL SOCIETY, vol. 54, no. 1, page. 381 - 385, 2009-01