2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/54030Talk given at the 7th Marcel Grossmann Meeting on General Relativity, Stanford University, July 24-30, 1994.Latex, 4p, MPI-PhT/94-66, ZU-TH 32/94High Energy Physics - TheoryBlack Holes and Sphalerons in Low Energy Effective String Theorytext