Information Processing Letters
Information Processing Letters > 2004 > 91 > 3 > 115-120
Information Processing Letters > 2008 > 108 > 4 > 251-254
Information Processing Letters > 2010 > 110 > 22 > 1021-1025
Information Processing Letters > 2004 > 91 > 3 > 115-120
Information Processing Letters > 2008 > 108 > 4 > 251-254
Information Processing Letters > 2010 > 110 > 22 > 1021-1025