Technical report on the Ruhr coalfield /
Great Britain.Ministry of Fuel and Power.Mechanisation Advisory Committee.
British Intelligence Objectives Sub-Committee.
London : H.M.S.O.,
1946-49.
Vols. 1 and 2 are B.I.O.S. final report no. 394; vol. 3, pt. 1 is B.I.O.S. final report no. 1330; vol. 3, pt. 2 is B.I.O.S. final report no. 1685.
v. 1 -- v. 2, pt. 1 -- v. 2, pt. 2 -- v3., pt. 1 -- v. 3, pt. 2 -- v. 3, appendices 1-30.
Coal mines and mining