Attfield, M. D. (1992). British data on coal miners' pneumoconiosis and relevance to US conditions.
Dyfyniad Arddull ChicagoAttfield, M D. British Data On Coal Miners' Pneumoconiosis and Relevance to US Conditions. 1992.
Dyfyniad MLAAttfield, M D. British Data On Coal Miners' Pneumoconiosis and Relevance to US Conditions. 1992.
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