4175 20190416153528.0 POSTER-2019-0086 Lefèvre, Laure The Sunspot Number Recalibration 2018 2018-10-29 BRAIN/ VAL-U-SUN/ VAL-U-SUN NO Clette, Frédéric Delouille, Véronique Mathieu, Sophie von Sachs, Rainer 2018 SDO Science Workshop laure.lefevre@observatoire.be CPOSTER