@article{v002a003,
 author = {Gupta, Anupam and Srinivasan, Aravind},
 title = {An Improved Approximation Ratio for the Covering Steiner Problem},
 year = {2006},
 pages = {53--64},
 doi = {10.4086/toc.2006.v002a003},
 publisher = {Theory of Computing},
 journal = {Theory of Computing},
 volume = {2},
 number = {3},
 URL = {https://theoryofcomputing.org/articles/v002a003},
}