The Reports of the Registrars-General for England and Wales, Scotland, Ireland, Saorstát Eireann, and Northern Ireland. The Annual Reports of the Superintendent M. O. H., Belfast. Belfast Health Commission's Report to the Local Government Board for Ireland, 1908.
2.
Darra MairL. W., Proc. Roy. Soc. Med., 1909, ii (Sect. Epid.), p. 187.
3.
Office International d'Hygiene Publique, 1923, Bulletin No. 9, tome 15.