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New aspects of mineral and water resources in the Netherlands : [a symposium entitled "Enkele nieuwe aspecten van delfstoffen in Nederland", The Hague on March 18th, 1972]
Sijp, J. W. C. M. van der, (1973)
Privatise coal achieving international competitiveness
Robinson, Colin, (1987)
Put pits into profit : alternative plan for coal
Boyfield, Keith, (1985)