Neutrino textures in light of Super-Kamiokande data and a realistic string model J. Ellis, G.K. Leontaris, S. Lola and D.V. Nanopoulos Eur. Phys. J. C, 9 3 (1999) 389-408 Published online: 18 June 1999 DOI: 10.1007/s100520050032