PIKETH, S. Message from the NACA President. Clean Air Journal, [S. l.], v. 29, n. 1, 2019. DOI: 10.17159/2410-972X/2019/v29n1a5. Disponível em: https://cleanairjournal.org.za/article/view/6889. Acesso em: 11 aug. 2022.