Suggested citation and version history for:  


  Grant, J.A., Wilson, S.A., Fortezzo, C.M., and 
       Clark, D.A., 2009, Geologic map of MTM-20012 and 
       -25012 quadrangles, Margaritifer Terra region of 
       Mars:  U.S. Geological Survey Scientific 
       Investigations Map 3041, Version 1.0, 1:1,000,000, 
       1 sheet and pamphlet 
       [http://pubs.usgs.gov/sim/3041/].


  Version 1.0, May 5, 2009

  Initial release online at
  http://pubs.usgs.gov/sim/3041/