Longwall retreat of gate road pillars
By: by J.M. Listak and E.R. Bauer.
Contributors: Bauer, Eric R.
Series: Report of investigations ;; 9444; Report of investigations (United States. Bureau of Mines) ;; 9444.
Publisher: U.S. Dept. of the Interior, Bureau of Mines
Published: 1993
Place of publication: Washington, D.C
Language: eng
Number of pages: 11
Subjects: Ground control (Mining) -- Pennsylvania.; Pillaring (Mining); Longwall mining -- Pennsylvania.; Gate roads (Mining) -- Pennsylvania.
Notes: Includes bibliographical references (p. 11).