@Article{acpd-9-12171-2009,
AUTHOR = {Zyrichidou, I. and Koukouli, M. E. and Balis, D. S. and Katragkou, E. and Melas, D. and Poupkou, A. and Kioutsioukis, I. and van der A, R. and Boersma, F. K. and van Roozendael, M. and Richter, A.},
TITLE = {Satellite NO$_{2}$ observations and model simulations of tropospheric  columns over South-eastern Europe},
JOURNAL = {Atmospheric Chemistry and Physics Discussions},
VOLUME = {9},
YEAR = {2009},
NUMBER = {3},
PAGES = {12171--12205},
URL = {http://www.atmos-chem-phys-discuss.net/9/12171/2009/},
DOI = {10.5194/acpd-9-12171-2009}
}