1. Solution of large scale transportation problems through aggregation;Balas;Operations Research,1965
2. Aggregation in transport networks: An Application of Hierarchical Structure;Chan;M.I.T. Dept. Civil Engng Res. Report No. R68-47,1968
3. Optimal travel time reduction in a transit network: An Application of Network Aggregation and Branch-and-Bound Techniques;Chan;Research Report R69-39, M.I.T. Dept. of Civil Engng,1969
4. An appraisal of some shortest-path algorithms;Dreyfus,1968
5. Flows in Networks;Ford,1962