Detection of spike-like structures near the front of type-II bursts S. Armatas, C. Bouratzis, A. Hillaris, C. E. Alissandrakis, P. Preka-Papadema, X. Moussas, E. Mitsakou, P. Tsitsipis and A. Kontogeorgos A&A, 624 (2019) A76 Published online: 11 April 2019 DOI: 10.1051/0004-6361/201834982