1. McHale, J., , The Ecological Context: Energy and Materials, World Design Science Decade, 1965–1975, Document 6, World Resources Inventory, Southern Ill. Univ., Carbondale, Ill., 1967,
2. Profile of pollutant fractions in nonurban suspended particulate matter, APCA Paper No. 96-165;McMullen,1969
3. Patterns and trends in levels of suspended particulate matter at 78 NASN sites from 1957 through 1966, APCA Paper No. 6908;Spirtus,1969