European Journal of Operational Research
European Journal of Operational Research > 1996 > 88 > 2 > 345-347
European Journal of Operational Research > 1996 > 94 > 1 > 87-96
European Journal of Operational Research > 1999 > 113 > 2 > 450-468
European Journal of Operational Research > 2000 > 125 > 2 > 425-428
European Journal of Operational Research > 2001 > 133 > 2 > 447-453