1. et al.Variations in Atmospheric Lead Concentrations and Type with Particle Size, SRI Project PA-4211Stanford Research Institute Menlo Park , Calif 1963 Nov 1 40
2. Robinson, E. and Ludwig, F.L. April 30 1964.Size Distribution of Atmospheric Lead Aerosols, SRI Project PA-4788, April 30, 2230Menlo Park, Calif: Stanford Research Institute.
3. Morrow, P.E. and Casarett, L.J. 1961.Inhaled Particles and Vapours, 167Oxford, England: Pergamon Press.
4. March 1966.Symposium on Environmental Lead ContaminationMarch, 43 US Department of Health, Education, and Welfare, Public Health Service, Publication No. 1440