Ionospheric f_oF2 Variations prior to strong earthquakes in Taiwan area,
Chuo, Y. J., Y. I. Chen, J. Y. Liu, S. A. Pulinets (2001),
Adv. Space Res., 27, 6–7 p. 1305–1310,
10.1016/S0273-1177(01)00209-5.