• publisher: Pittsburgh, PA : U.S. Dept. of the Interior, Bureau of Mines
  • creator: Barrett, Edward A Wiehagen, William J Peters, Robert H
  • contributor: Wiehagen, William J. Peters, Robert H.
  • Keyword: Mine safety Study and teaching Audio-visual aids. Ground control (Mining) Mine roof control. Transparencies in education. Photography, Stereoscopic.
  • years: 1988.
  • pages: 15 p. :
  • class: TN295
  • download: pdf file