2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/62795Divisorial contractions to singularities, defined by equations $xy+z^n+u^n=0$ $n\ge3$ and $xy+z^3+u^4=0$ are classified.10 pages, 1 figireAlgebraic Geometry14E30text