1. Pott P.Chirurgical works.London: Hawes, W Clarke, R Collins, 1775.
2. Hunter D.The diseases of occupations.5th edition. London: EUP, 1975: 145.
3. Kingsley C.Water babies.1863.
4. Chief Inspector of Factories.Annual Reports.London: HMSO, 1835–1880.
5. Gaskell E.North and south.1855 (Penguin Edition 1979): 146.