1. http://www.cmhrc.co.uk/site/literature/royalcommissionreports/
2. Pneumoconiosis of coal-miners;Fletcher;Br Med J,1948
3. Effects of dust upon coal trimmers;Collis;J Indust Hyg,1928
4. Hart P d'A , Aslett EA . Chronic pulmonary disease in South Wales coalminers 1. Medical studies. MRC Special Report Series 243, London, 1942.
5. Pneumoconiosis of coal trimmers;Gough;J Path Bact,1940