1. Commercial software for locating warehouses and other facilities;Ballou;Journal of Business Logistics,1993
2. Barcos, L., 2002. Routing optimization for many-to-many freight transportation systems using Ant Colony Optimization. PhD thesis, Tecnun, University of Navarra (in Spanish).
3. Applying the ant system to the vehicle routing problem;Bullnheimer,1999
4. Rail tactical planning: issues, models and tools;Crainic,1988
5. Crainic, T.G., 2002. A survey of optimization models for long-haul freight transportation. CRT-2002-05, Centre de recherché sur les transports, Université de Montréal.