Christian Icking Rolf Klein Elmar Langetepe Sven Schuierer Ines Semrau An Optimal Competitive Strategy for Walking in Streets. 462-486 2004 33 SIAM J. Comput. 2 http://dx.doi.org/10.1137/S0097539702419352 db/journals/siamcomp/siamcomp33.html#IckingKLSS04