1. 1938 Climate of the British Isles, London (MacMillan), p. 59.
2. 1947 Proc. Edin. Conf., National Smoke Abatement Society, London, p. 99.
3. and 1938 Trans. Highland & Agric. Soc. of Scotland, Edinburgh (W. Blackwood & Sons), 50, p. 184.
4. Leicester Report 1945 Atmospheric Pollution in Leicester, H.M. Stationery Office, pp. 128 and 131.