Revision History for USGS 
  Crustal Studies Technical Letter Number 0013

  J.H. Healy and G.B. Mangan

  Preliminary Study of First Motion from Nuclear Explosions 
  Recorded on Seismograms in the First Zone

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  Posted online at http://pubs.usgs.gov/misc/tl/0013/
  August 6, 2012

  Initial release in paper form
  August 23, 1963

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