The Planeterrella experiment: from individual initiative to networkingJean Lilensten, Gabrielle Provan, Sandrine Grimald, Asgeir Brekke, Erwin Flückiger, Petra Vanlommel, Cyril Simon Wedlund, Mathieu Barthélémy and Pierre GarnierJ. Space Weather Space Clim., 3 (2013) A07DOI: https://doi.org/10.1051/swsc/2013029