Ingo Demgensky Hartmut Noltemeier Hans-Christoph Wirth Optimizing Cost Flows by Modifying Arc Costs and Capacities. 116-126 http://link.springer.de/link/service/series/0558/bibs/1928/19280116.htm 2000 conf/wg/2000 WG db/conf/wg/wg2000.html#DemgenskyNW00