@article{CTT100550520,
  author = {Heiga Zen and Keiichi Tokuda and Takashi Masuko and Takao Kobayashi and Tadashi Kitamura},
  title = {A Hidden semi-Markov model-based speech synthesis system},
  journal = {IEICE Trans. on Information and Systems},
  year = 2007,
}

@article{CTT100550519,
  author = {Heiga Zen and Takashi Masuko and Keiichi Tokuda and Takashi Yoshimura and Takao Kobayashi and Tadashi Kitamura},
  title = {State duration modeling for HMM-based speech synthesis},
  journal = {IEICE Trans. on Information and Systems},
  year = 2007,
}