@article{CTT100588771,
  author = {Ryoso Hamane and Toshiya Itoh and Kouhei Tomita},
  title = {Approximation Algorithms for the Highway Problem under the Coupon Model},
  journal = {IEICE Trans. on Fundamentals},
  year = 2009,
}

@article{CTT100570498,
  author = {Ryoso Hamane and Toshiya Itoh and Kouhei Tomita},
  title = {Approximation Preserving Reductions among Item Pricing Problems},
  journal = {IEIC Transactions on Information and Systems},
  year = 2009,
}

@inproceedings{CTT100570468,
  author = {富田紘平 and 高村大也 and 奥村学},
  title = {重要文抽出と文圧縮を組み合わせた新たな抽出的要約手法},
  booktitle = {},
  year = 2009,
}

@misc{CTT100547501,
  author = {Ryoso Hamane and Toshiya Itoh and Kouhei Tomita},
  title = {Approximation Algorithms for the Highway Problem under the Coupon Model},
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}