Lepton and baryon number violation in particle physics, astrophysics, and cosmology proceedings of the First International Symposium on Lepton and Baryon Number Violation (Lepton-Baryon 98), European Centre for Theoretical Physics, Trento, Italy, 20-25 April 1998 / - Klapdor-Kleingrothaus, H. V.; Krivosheina, I. V. (Institute of Physics Pub.,)