1. Gell RRA, Coombs PGH. Classification of allergic reactions responsible for clinical hypersensitivity disease. In: Gell PGH, Coombs RRA, eds. Clinical aspects of immunology. 2d ed. Oxford, Blackwell, 1968: 575–596.
2. Campbell JM. Acute symptoms following work with hay. Br Med J 1932; 2: 1143–1144.
3. Fawcitt R. Fungoid conditions of the lung. Br J Radiol 1936;9: 172–195; 354–378.
4. Tornell E. Thresher’s lung. Acta Med Scand. 1946; 125: 191–219.
5. Pepys J, Riddell RW, Citron KM, Clayton YM. Precipitins against extracts of hay and moulds in the serum of patients with farmer’s lung, aspergillosis, asthma and sarcoidosis. Thorax 1962; 17: 366–374.