1. G.A. Klunder, H.N. Post, The Shortest Path Problem on Large-Scale Real-Road Networks (2006)
2. M. Muller-Hannemann, M. Schnee, Finding All Attractive Train Connections by Multicriteria Pareto Search. in Algorithmic Methods for Railway Optimization (2007)
3. F. Schulz, D. Wagner, C. Zaroliagis, Using Multi-Level Graphs for Timetable Information in Railway Systems. Algorithm Engineering and Experiments (2002)
4. J.-P. Rodrigue, C. Comtois, B. Slack, The Geography of Transport Systems, 2nd edn. (Routledge, New York, 2009).
5. T. Pajor, Multi-Modal Route Planning. Universitat Karlsruhe (2009)