@ARTICLE{Saegusa2003,
  author = {Saegusa, Ryo and Sakano, Hitoshi and Hashimoto, Shuji},
  title = {Nonlinear Principal Component Analysis to Preserve the Order of Principal Components (In Japanese)},
  journal = {The transactions of the Institute of Electronics, Information and	Communication Engineers},
  year = {2003},
  volume = {J86-D-II},
  pages = {943-950},
  number = {7}
}