Katarzyna Paluch Marcin Mucha Aleksander Madry A 7/9 - Approximation Algorithm for the Maximum Traveling Salesman Problem. 298-311 2009 APPROX-RANDOM http://dx.doi.org/10.1007/978-3-642-03685-9_23 conf/approx/2009 db/conf/approx/approx2009.html#PaluchMM09