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@rmark

@rmark

Joined over 7 years ago

MS Physics, Ph.D. Geology, retired from US Geological Survey. Now, Chief Scientist, Rupestrian CyberServices (RCS) http://www.rupestrian.com RCS works to document and protect rock art.

See also http://www.rupestrian.com/robert-mark.html and http://www.rupestrian.com/publications.html