Buitink, S., Corstanje, A., Falcke, H., Hörandel, J. R., Huege, T., Nelles, A., et al. (2016). A large light-mass component of cosmic rays at 10(17)–10(17.5) electronvolts from radio observations. Nature, 531(7592), 70-73. doi:10.1038/nature16976.