The ionospheric precursor to the 2011 march 11 earthquake as based on the Japan-pacific subionospheric VLF/LF network observation - M. Hayakawa; Y. Hobara; A. Rozhnoi; M. Solovieva; K. Ohta; J. Izutsu; T. Nakamura; Y. Yasuda; H. Yama-guchi; Y. Kasahara (Radiophysics and Electronics, 2012)