Control of coherence in excitable systems by the interplay of noise and time-delay N. Kouvaris, L. Schimansky-Geier and E. Schöll Eur. Phys. J. Special Topics, 191 (2010) 29-51 Published online: 18 February 2011 DOI: 10.1140/epjst/e2010-01340-x