Neugebauer, M., Neubauer, F. M., Balsiger, H., Fuselier, S. A., Goldstein, B. E., Goldstein, R., Mariani, F., Rosenbauer, H., Schwenn, R., & Shelley, E. G. (1987). The variation of protons, alpha particles, and the magnetic field across the bow shock of comet Halley. Geophysical Research Letters, 14, 995-998.