Raistric, A. (1939). Nature and origin of coal and coal seams. The English University press.
Dyfyniad Arddull ChicagoRaistric, A. Nature and Origin of Coal and Coal Seams. LOndon: The English University press, 1939.
Dyfyniad MLARaistric, A. Nature and Origin of Coal and Coal Seams. The English University press, 1939.
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