Monnot, Jérôme; Paschos, Vangelis Th.; Toulouse, Sophie - In: Mathematical Methods of Operations Research 56 (2003) 3, pp. 387-405
We first prove that the minimum and maximum traveling salesman problems, their metric versions as well as some versions defined on parameterized triangle inequalities (called sharpened and relaxed metric traveling salesman) are all equi-approximable under an approximation measure, called...