WMO/GAW expert workshop on global long-term measurements of nitrogen oxides and recommendations for GAW nitrogen oxides network. Hohenpeissenberg, Germany, 8-9 October 2009.

Penkett, S.; Gilge, S.; Plass-Duelmer, C.; Galbally, I.; Brough, N.; Bottenheim, J.; Flock, F.; Gerwig, H.; Lee, J.; Milton, M.; Rohrer, F.; Ryerson, T.; Steinbacher, M.; Tørseth, K.; Wielgosz, R.