IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, vol. 51, no. 4, page. 930 - 933, 2004-08
INTERNATIONAL JOURNAL OF ELECTRONICS, vol. 91, no. 7, page. 385 - 405, 2004-07
IEE PROCEEDINGS-ELECTRIC POWER APPLICATIONS, vol. 151, no. 1, page. 91 - 97, 2004-01