Boris Goldengorin Gerard Sierksma Marcel Turkensteen Tolerance Based Algorithms for the ATSP. 222-234 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3353&spage=222 2004 conf/wg/2004 WG db/conf/wg/wg2004.html#GoldengorinST04