Reuven Bar-Yehuda Dror Rawitz On the Equivalence between the Primal-Dual Schema and the Local-Ratio Technique. 24-35 2001 conf/random/2001 RANDOM-APPROX http://link.springer.de/link/service/series/0558/bibs/2129/21290024.htm db/conf/random/random2001.html#Bar-YehudaR01