ELECTRONICS LETTERS, vol. 40, no. 19, page. 1211 - 1212, 2004-09-16
ELECTRONICS LETTERS, vol. 40, no. 5, page. 330 - 331, 2004-03-04
IEEE PHOTONICS TECHNOLOGY LETTERS, vol. 16, no. 2, page. 593 - 595, 2004-02