2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/67367Automatic groups admitting prefix closed automatic structures with uniqueness are characterized as the quotients of free groups by normal subgroups possessing sets of free generators satisfying certain language-theoretic conditions.14 pages, no figures. Minor corrections. Statements of theorems and lemmas are unchangedGroup Theory20F65; 68Q45text