Preliminary results on photometric properties of materials at the Sagan Memorial Station, Mars

Jeffrey R. Johnson, Randolph Kirk, Laurence A. Soderblom, Lisa Gaddis, Robert J. Reid, Daniel T. Britt, Peter Smith, Mark Lemmon, Nicolas Thomas, James F. Bell, Nathan T. Bridges, Robert Anderson, Ken E. Herkenhoff, Justin Maki, Scott Murchie, Andreas Dummel, Ralf Jaumann, Frank Trauthan, Gabriele Arnold