Fujinawa, Y., and K. Takahashi, Anomalous VLF subsurface electric field changes preceding earthquakes, in Electromagnetic Phenomena Related to Earthquake Prediction, pp. 131-147, Terra Scientific Publishing Co., Tokyo, 1994.
Fujinawa, Y. and K. Takahashi, Characteristics of anomalous electric field changes at the time of 1995 Hyogo-ken Nanbu Earthquake, Gekkan Ghikyu (Spec. Ed.), 13, 175-184, 1995 (in Japanese).