Roof rock structures and related roof support problems in the Pittsburgh coalbeds of southwestern Pennsylvania /

Bibliographic Details
Main Author:	Moebs, Noel N.
Corporate Author:	United States. Bureau of Mines
Format:	Government Document Book
Language:	English
Published:	[Washington] : Dept. of the Interior, Bureau of Mines, 1977.
Series:	Report of investigations (United States. Bureau of Mines) ; 8230.
Subjects:	Coal > Geology > Pennsylvania > Pittsburgh. Mine timbering. Mine roof bolting.

Description
Physical Description:	2 unnumbered pages, ii, 30 pages : illustrations, maps ; 27 cm.
Bibliography:	Includes bibliographical references and appendix.