Identifying the Main Sources of Brown Carbon in the Atmosphere. IMAD EL HADDAD, Nivedita Kumar, Joel Corbin, Kaspar Rudolf Daellenbach, Dario Massabò, Emily Bruns, Athanasia Vlachou, Carlo Bozzetti, Jay Slowik, Paolo Prati, Urs Baltensperger, Jean-Luc Jaffrezo, Luka Drinovec, Grisa Mocnik, Martin Gysel, Andre Prévôt, Paul Scherrer Institute