Here's one: "MARS EXPRESS HRSC COLORS OF WHITE ROCK, ARABIA, MARS."
Raitala J. Basilevsky A. T. Neukum G. Werner S. C. Denk T. McCord T. B. HRSC C-Investgator Team
Mars Express HRSC Colors of White Rock, Arabia, Mars [#1710]
The MEX HRSC spectral data suggest (but not prove) that White Rock may be evaporite deposit resembling the Opportunity sulfate deposits.
http://www.lpi.usra.edu/meetings/lpsc2005/pdf/1710.pdf
Bob Clark
