First recorded eruption of Nabro volcano, Eritrea, 2011 - Goitom, B; Oppenheimer, C; Hammond, JOS; Grandin, R; Barnie, T; Donovan, A; Ogubazghi, G; Yohannes, E; Kibrom, G; Kendall, J-M; Carn, SA; Fee, D; et al. (Bulletin of Volcanology, 2015)