INTERNATIONAL JOURNAL OF CONTROL, vol. 65, no. 6, page. 913 - 924, 1996-12
IEEE TRANSACTIONS ON AUTOMATIC CONTROL, vol. 41, no. 12, page. 1799 - 1802, 1996-12
IEEE TRANSACTIONS ON AUTOMATIC CONTROL, vol. 41, no. 5, page. 727 - 732, 1996-05
THE CONTROL HANDBOOK, page. 1243 - 1259, 1996-01