2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/68470These are (not updated) notes from the lectures I gave in St.Petersburg in July of 2001. Their goal is to give an expository account of the proof of Kontsevich's combinatorial formula for intersections on moduli spaces of curves following math.AG/0101147.44 pages, 22 figuresCombinatoricsAlgebraic Geometrytext