EXOS-D (AKEBONO) very low frequency plasma wave instruments (VLF). - Kozo Hashimoto; Isamu Nagano; Masayuki Yamamoto; Toshimi Okada; Iwane Kimura; Hiroshi Matsumoto; Hidetaka Oki (IEEE Trans. Geosci. Remote. Sens., 1997)

A modified error backpropagation algorithm for complex-value neural networks. - Xiaoming Chen; Zheng Tang; Catherine Vairappan; Songsong Li; Toshimi Okada (Int. J. Neural Syst., 2005)

An Individual Adaptive Gain Parameter Backpropagation Algorithm for Complex-Valued Neural Networks. - Songsong Li; Toshimi Okada; Xiaoming Chen; Zheng Tang (ISNN (1), 2006)