| Bulgaria | INRNE | Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Science, Sofia |
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| Czech Republic | ICPF AS CR | Institute of Chemical Process Fundamentals, Prague |
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| Finland | UHEL | University of Helsinki, Helsinki |
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| Finland | FMI | Finnish Meteorological Institute, Helsinki |
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| France | CNRS-LaMP | Centre National de la Recherche Scientifique, Clermont-Ferrand |
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| Germany | IFT | Leibniz Institute for Tropospheric research, Leipzig |
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| Germany | UHEI | Ruprecht-Karls-Universitat Heidelberg, Heidelberg |
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| Germany | HMT | Hoffmann Messtechnik GmbH, Rauenberg |
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| Greece | UOC | University of Crete, Heraklion |
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| Hungary | ACUV | University of Veszprém, Veszprem |
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| Ireland | NUIG | National University of Ireland, Galway |
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| Italy | EC-DG JRC | European Commission - Joint Research Centre, Ispra |
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| Italy | ISAC-CNR | Consiglio Nazionale delle Ricerche, ISAC, Bologna |
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| Lithuania | IPL | Institute of Physics, Vilnius |
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| Netherlands | TNO | Netherlands Organisation for Applied Scientific Research, The Hague |
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| Norway | NILU | Norwegian Institute for Air Research, Kjeller |
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| Spain | CSIC-IES | Consejo Superior de Investigaciones Científicas, Institute of Earth Sciences, Barcelona |
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| Sweden | ULUND | Lund University, Lund |
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| Sweden | SU | Stockholms Universitet, Stockholm |
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| Switzerland | PSI | Paul-Scherrer-Institut, Villigen |
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| United Kingdom | UNI BHAM | The University of Birmingham, Birmingham |
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