(** * ∑-precategories *) (** These are a generalization of subcategories in the direction of the Grothendieck construction *)Require Category.Sigma.OnMorphisms. Require Category.Sigma.OnObjects. Require Category.Sigma.Univalent. Include Category.Sigma.Core. Include Category.Sigma.OnMorphisms. Include Category.Sigma.OnObjects. Include Category.Sigma.Univalent. Module CategorySigmaNotations. Include Category.Sigma.OnObjects.CategorySigmaOnObjectsNotations. End CategorySigmaNotations.