Anthracite Mechanical-Mining Investigations
Subtitle: Progress Report 7: Longhole Retreat Mining of A Steeply Pitching Anthracite Bed.
Contributors: Allan, A.; Davies, R.
Series: Report of investigations (United States. Bureau of Mines) -- 4925
Publisher: s.n
Published: 1953
Place of publication: S.l
Language: eng
Notes: 1