Colwill, D. M., Butler, J. D., & Crossley, P. (1981). Polynuclear aromatic hydrocarbons in the atmosphere in Birmingham. Transport and Road Research Laboratory.
Chicago-viite (17. p.)Colwill, D. M., J. D. Butler, ja P. Crossley. Polynuclear Aromatic Hydrocarbons in the Atmosphere in Birmingham. Crowthorne, Berkshire: Transport and Road Research Laboratory, 1981.
MLA-viite (9. p.)Colwill, D. M., et al. Polynuclear Aromatic Hydrocarbons in the Atmosphere in Birmingham. Transport and Road Research Laboratory, 1981.
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