Multi-ring signatures of the oscillation in a water Cherenkov detector A. E. Asratyan, G. V. Davidenko, A. G. Dolgolenko, V. S. Kaftanov, M. A. Kubantsev and V. S. Verebryusov Eur. Phys. J. C, 31 1 (2003) 31-36 Published online: 26 September 2003 DOI: 10.1140/epjc/s2003-01285-2