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;
Baumjohann, W., Pellinen, R. J., Opgenoorth, H. J., & Nielsen, E. (1981). Joint two-dimensional observations of ground magnetic and ionospheric electric fields associated with auroral zone currents. 4. Current system associated with local auroral breakups. Planetary and Space Science, 29, 431.