机译:Inapproximability of Maximum r-Regular Induced Connected Subgraph Problems*
The authors are with the Department of System Design and Informatics, Kyushu Institute of Technology, Iizuka-shi, 820-8502 Japan;
The authqr is with the Department of Information Science,Kyushu Sangyo University, Fukuoka-shi, 813-8503 Japan;
induced connected subgraph; regularity; NP-hardness; inapproximability;