Christensen, U. R. Department Planets and Comets, Max Planck Institute for Solar System Research, Max Planck Society; MPI for Aeronomy, Max Planck Institute for Solar System Research, Max Planck Society;
Christensen, U. R., & Olson, P. (2003). Secular variation in numerical geodynamo models with lateral variations of boundary heat flow. Physics of the Earth and Planetary Interiors, 138, 39-54.