Revision History for USGS 
  Crustal Studies Technical Letter Number 8

  L.C. Pakiser

  Structure of the Crust and Upper Mantle in the Western 
  United States

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  Posted online at http://pubs.usgs.gov/misc/tl/0008/
  July 27, 2012

  Initial release in paper form
  January 28, 1963

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