Eric Angel, Evripidis Bampis, Laurent Gourvès, Jérôme Monnot. (Non)-Approximability for the Multi-criteria ::::TSP::::(1, 2). In Maciej Liskiewicz, Rüdiger Reischuk, editors, Fundamentals of Computation Theory, 15th International Symposium, FCT 2005, Lübeck, Germany, August 17-20, 2005, Proceedings. Volume 3623 of Lecture Notes in Computer Science, pages 329-340, Springer, 2005. [doi]
Abstract is missing.