Nielsen, E. MPI for Aeronomy, Max Planck Institute for Solar System Research, Max Planck Society; Department Planets and Comets, Max Planck Institute for Solar System Research, Max Planck Society;
Lewis, R. V., Williams, P. J. S., Yeoman, T. K., Lester, M., & Nielsen, E. (1993). Measurements of bursts in plasma velocity during substorm activity. Advances in Space Research, 13, (4)139-(4)142.