TY - JOUR A1 - Liu, H. Z. A1 - Feng, J. W. A1 - Järvi, L. A1 - Vesala, T. T1 - Four-year (2006–2009) eddy covariance measurements of CO2 flux over an urban area in Beijing JO - Atmos. Chem. Phys. J1 - ACP VL - 12 IS - 17 SP - 7881 EP - 7892 Y1 - 2012/09/03 PB - Copernicus Publications SN - 1680-7324 UR - http://www.atmos-chem-phys.net/12/7881/2012/ L1 - http://www.atmos-chem-phys.net/12/7881/2012/acp-12-7881-2012.pdf DO - 10.5194/acp-12-7881-2012 ER -