Item from Mathematical Reviews (American Mathematical Society)--access
their stable url through the AMS database via an institutional library:
MR2147040 (2006a:90046) Berman, Oded; Krass, Dmitry An improved IP
formulation for the uncapacitated facility location problem:
capitalizing on objective function structure. Ann. Oper. Res. 136
(2005), 21--34. (Reviewer: Sandra L. Arlinghaus) 90B80 (90C10)