European Journal of Operational Research
European Journal of Operational Research > 2002 > 139 > 2 > 390-399
European Journal of Operational Research > 2002 > 139 > 3 > 533-542
European Journal of Operational Research > 2002 > 139 > 2 > 390-399
European Journal of Operational Research > 2002 > 139 > 3 > 533-542