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2. The effects of trees on the urban climate;Bernatzky,1983
3. Bolund, P., 1996. Ecological Problems Caused by Roads and Railroads. Master Thesis 1996:20. Department of Systems Ecology, Stockholm University, 30 pp.
4. Cities as environments;Botkin;Urban Ecosystems,1997
5. Bramryd, T., Fransman, B., 1993. Stadens lungor- om luftkvaliteten och växtligheten i våra tätorter (The lungs of the city—on air quality and vegetation in our cities). Movium-SLU Stad och Land 116, Alnarp (quoted from Svensson and Eliasson 1997; in Swedish).