Peng Cui. A Tighter Analysis of Set Cover Greedy Algorithm for Test Set. In Bo Chen, Mike Paterson, Guochuan Zhang, editors, Combinatorics, Algorithms, Probabilistic and Experimental Methodologies, First International Symposium, ESCAPE 2007, Hangzhou, China, April 7-9, 2007, Revised Selected Papers. Volume 4614 of Lecture Notes in Computer Science, pages 24-35, Springer, 2007. [doi]