Haaland, S. Space Plasma Physics of Near-Earth Environment, MPI for Extraterrestrial Physics, Max Planck Society;
Dunlop, M. W., Balogh, A., Shi, Q.-Q., Pu, Z., Vallat, C., Robert, P., et al. (2006). The curlometer and other gradient measurements with cluster. In Proceedings of the Cluster and Double Star Symposium: 5th Anniversary of Cluster in Space. Noordwijk, The Netherlands: ESA Publications Division.