Mass composition working group reportE. Barcikowski, J. Bellido, J. Belz, Y. Egorov, S. Knurenko, V. de Souza, Y. Tameda, Y. Tsunesada and M. UngerEPJ Web of Conferences, 53 (2013) 01006DOI: https://doi.org/10.1051/epjconf/20135301006