Vincenzo Auletta Yefim Dinitz Zeev Nutov Domenico Parente A 2-Approximation Algorithm for Finding an Optimum 3-Vertex-Connected Spanning Subgraph. 21-30 1999 32 J. Algorithms 1 db/journals/jal/jal32.html#AulettaDNP99 http://dx.doi.org/10.1006/jagm.1999.1006