I would like to know that too.
Regarding MODFLOW - thats a free product of US-GS and one of the
later reports on this program (PCG2 solver) says:
copies of this report can be pourchsed from:
US-GS
Books and Open-File Reports section
Box 25425
Federal Center
Denver, CO, 80225-0425
Perhaps they would send you a catalog.
Hope this helps. Peter. pom@llnl.gov
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