NOTE: These materials are based upon work supported by the National Science Foundation under Grants No. 0723437, 0725998, and 0744187. Any opinions, findings, and conclusions or recommendations expressed in these materials are those of the authors and do not necessarily reflect the views of the National Science Foundation. For information about this initiative, email Lee.allison at azgs.az.gov | Copyright © Geoinformatics.info, 2007  |