@article{CTT100552022,
  author = {J. Sugiyama and T. Nakamura and Noriyoshi Ishii and T. Nishikawa and M. Oka},
  title = {Mixings of 4-quark components in light non-singlet scalar mesons in QCD sum rules},
  journal = {Physical Review},
  year = 2008,
}

@article{CTT100598876,
  author = {T. Nakamura and J. Sugiyama and T. Nishikawa and M. Oka and N. Ishii},
  title = {Exotic quark structure of Lambda(1405) in QCD sum rule},
  journal = {Physics Letters},
  year = 2008,
}