1. Observations and theory of the AMPTE magnetotail barium releases
2. W.-H. Ip and W. I. Axford, inComets, edited by L. L. Wilkening (University of Arizona Press, Tucson, 1982), p. 588.
3. Television observations of comet Halley from Vega spacecraft
4. Magnetic field observations in comet Halley's coma
5. D. A. Tidman and N. A. Krall,Shock Waves in Collisionless Plasmas(Wiley, New York, 1971).