1. Finding a cycle in a graph with minimum cost to time ratio with application to a ship routing problem;Danzig,1967
2. Algorithms for shortest paths;Johnson,1973
3. Optimal cycles in doubly weighted linear graphs;Lawler,1967
4. Combinatorial Optimization: Networks and Matroids;Lawler,1976
5. Optimization of stationary control of a discrete deterministic process;Romanovskii;Cybernetics,1967