J. M. Rogan, J. R. Ashford, P. J. Chapman, D. P. Duffield, J. W. J. Fay, S. Rae et al
Rogan J M, Ashford J R, Chapman P J, Duffield D P, Fay J W J, Rae S et al.
Pneumoconiosis and Respiratory Symptoms in Miners at Eight Collieries
Br Med J 1961; 1 :1337
doi:10.1136/bmj.1.5236.1337