1. EPA Technical Bulletin, Nitrogen Oxides (NO
x), Why and How They Are Controlled?
https://www3.epa.gov/ttncatc1/dir1/fnoxdoc.pdf. Accessed 5 Oct 2019
2. World Health Organization, Nitrogen Dioxide, Global Update (World Health Organization, Regional Office for Europe, Copenhagen, 2005)
3. European Environment Agency, Air Quality in Europe—2012 Report, EEA Report No. 4/2012 (European Environment Agency, 2012)
4. N.N. Hansel, P.N. Breysse, M.C. McCormack, E.C. Matsui, J. Curtin-Brosnan, D.L. Williams, J.L. Moore, J.L. Cuhran, G.B. Diette, Environ. Health Perspect. 116, 1428 (2008)
5. Air Pollution in Europe 1990–2004, EU Air Quality Directive 2001/81/CE