Thomas, N. MPI for Aeronomy, Max Planck Institute for Solar System Research, Max Planck Society;
Johnson, J., Kirk, R., Sonderblom, L. A., Gaddis, L., Reid, R. J., Britt, D. T., et al. (1999). Photometric properties of materiels at the Sagan Memorial Station, Mars. Journal Geophysical Research, 104, 8809-8830.