Citizen Science Strategies in Europe : preliminary findings from the pan-European Survey of Citizen Science Strategies and initiatives in Europe as part of a joint initiative of the COST ACTION 15212 and the JRC discussed in Cēsis, Latvia, 4th June 2019 - Manzoni, Marina; Vohland, Katrin; Göbel, Claudia; Pruse, Baiba; Schade, Sven (2019)