Silicosis : report by E. L. Middleton, M.D., H.M. Medical Inspector of Factories, on the International Conference held at Johannesburg in August, 1930 /
Middleton, E. L.,author.
Great Britain.Home Office.
Great Britain.His Majesty's Stationery Office,issuing body.
International Conference on Silicosis(1930 :Johannesburg)