Systems & Control Letters
Systems & Control Letters > 1995 > 24 > 3 > 167-172
Systems & Control Letters > 1995 > 25 > 3 > 199-204
Systems & Control Letters > 1997 > 30 > 1 > 19-24
Systems & Control Letters > 1997 > 31 > 1 > 11-20
Systems & Control Letters > 1997 > 32 > 5 > 335-344