JOURNAL OF THE KOREAN PHYSICAL SOCIETY, vol. 39, no. 3, page. 568 - 571, 2001-09
IEICE TRANSACTIONS ON ELECTRONICS, vol. E84C, no. 8, page. 1104 - 1110, 2001-08
JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS, vol. 40, no. 3B, page. 2054 - 2057, 2001-03
ELECTRONICS LETTERS, vol. 37, no. 5, page. 322 - 323, 2001-03-01