Systems & Control Letters
Systems & Control Letters > 1996 > 27 > 3 > 187-190
Systems & Control Letters > 1996 > 28 > 3 > 173-179
Systems & Control Letters > 1996 > 29 > 2 > 119-120
Systems & Control Letters > 1996 > 29 > 2 > 61-72
Systems & Control Letters > 1996 > 29 > 3 > 175-180