1. Computers and Intractability: A guide to the Theory of NP-Completeness;Garey,1979
2. Lagrangean relaxation;Beasley,1993
3. An analysis of network location problems with distance constraints;Moon;Management Science,1984
4. Using proximity restrictions for locating undesirable facilities;Murray;Studies in Locational Analysis,1996
5. Integer and Combinatorial Optimization;Nemhauser,1988