2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/103675The author constructs a theory of dagger formal schemes over $R$ and then defines the de Rham cohomology for flat dagger formal schemes $X$ with integral and regular reductions $\bar{X}$ which generalizes the Monsky-Washnitzer cohomology. Finally the author gets Lefschetz' fixed pointed formula for $X$ with certain conditions.16 pagesAlgebraic Geometry11G25, 11M38text