WALKER, N.P.; ELLERBECK, R.H.; KEMENY, E. NATIONAL SURVEY OF SMOKE AND SULPHUR DIOXIDE : QUALITY OF SMOKE MEASUREMENTS. Clean Air Journal, [S. l.], v. 7, n. 1, p. 27–29, 1986. DOI: 10.17159/caj/1986/7/1.7346. Disponível em: https://cleanairjournal.org.za/article/view/7346. Acesso em: 3 may. 2024.