European Journal of Operational Research
European Journal of Operational Research > 1999 > 117 > 1 > 1-14
European Journal of Operational Research > 1999 > 117 > 2 > 310-325
European Journal of Operational Research > 1999 > 117 > 1 > 1-14
European Journal of Operational Research > 1999 > 117 > 2 > 310-325