Hviid, S. F. Department Planets and Comets, Max Planck Institute for Solar System Research, Max Planck Society;
Luethi, B. S., Thomas, N., Hviid, S. F., & Rueffer, P. (2010). An efficient autofocus algorithm for a visible microscope on a Mars lander. Planetary and Space Science, 58(10), 1258-1264. doi:10.1016/j.pss.2010.05.002.