3[1]Williams E R. The tripole structure of thunderstorms[J]. J Geophys Res, 1989, 94: 13151-13167
4[2]Reynolds S E, M Brook, M F Gourley. Thunderstorm charge separation[J]. J Meteor, 1957, 14: 426-437
5[3]Jayaratne E R, C P R Saunders, J Hallett. Laboratory studies of the charging of soft hail during ice crystal interactions[J]. Quart J Roy Meteor Soc, 1983, 109: 609-630
6[4]Takahashi T. Riming electrification as a charge generation mechanism in thunderstorms[J]. J Atmos Sci, 1978, 35: 1536-1548
7[5]Saunders C P R, W D Keith, R P Mitzeva. The effect of liquid water on thunderstorm charging[J]. J Geophys Res, 1991, 96: 11007-11017
8[6]Marshall B J P, J Latham, C P R Saunders. A laboratory study of charge transfer accompanying the collision of ice crystals with a simulated hailstone[J]. Quart J Roy Meteor Soc, 1978, 104: 163-178
9[7]Gaskell W, A J Illingworth. Charge transfer accompanying individual collisions between ice particles and its role in thunderstorm electrification[J]. Quart J Roy Meteor Soc, 1980, 106: 841-854
10[8]Avila E E, J M Caranti, M Lamfri. Charge reversal in individual ice-ice collisions[C]. Proc. Int. Conf. Atmos. Electr., Inst. High Voltage Research, Uppsala, 1988. 245-250