Ciais, P, Apadula, F, Brandt, J, Ciattaglia, L, Haszpra, L, Leuenberger, M C, Levin, I, Heimann, M, Hutjes, R W A, Meijer, H, Moncrieff, J & Vermeulen, A T 2002, AEROCARB, Second Periodic Report, Contract No. EVK2-CT-1999-00013 . European Commision .