01106nam a22003137a 4500001000600000003000600006005001700012008004100029040001700070082001500087100005400102245008500156260005700241300004500298336002600343337002800369338002700397500003000424500010300454504002800557650001300585650001500598650002900613650003600642650002800678650002800706700002600734700003200760u6119SIRSI20250825175116.0240904s1977    xxuao   r     000|0deng d  dclrauoherda04a624.192201 aProctor, Robert V.q(Robert Videtto),d1890-1967.10aEarth tunneling with steel supports /cby Robert V. Proctor and Thomas L. White.  aYoungstown, Ohio :bCommercial Shearing,Inc,cc1977.  a247 pages :billustrations, photographs.  atextbtxt2rdacontent  aunmediatedbn2rdamedia  avolumebnc2rdacarrier  aGlossary : pages 245-247.  alas secciones relacionadas con las investigaciones geologicas fueron preparadas por Karl Terzaghi.  aReferences : pages 244. 7aTunnels. 7aTúneles. 7aGround control (Mining). 7aControl de tierras (Minería). 7aGeología estructural. 7aGeología estructural.10aWhite, Thomas Lester.10aTerzaghi, Karl,d1883-1963.