Lukasz Kowalik Marcin Mucha Deterministic 7/8-Approximation for the Metric Maximum TSP. 132-145 2008 APPROX-RANDOM http://dx.doi.org/10.1007/978-3-540-85363-3_11 conf/approx/2008 db/conf/approx/approx2008.html#KowalikM08