Smoking is associated with an age-related decline in exhaled nitric oxide
J. S. Sundy, D. W. Hauswirth, S. Mervin-Blake, C. A. Fernandez, K. B. Patch, K. M. Alexander, S. Allgood, P. D. McNair, M. C. Levesque
European Respiratory Journal Dec 2007, 30 (6) 1074-1081; DOI: 10.1183/09031936.00087807