2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/111693We provide a complete description of the category of pseudo-categories (including pseudo-functors, natural and pseudo-natural transformations and pseudo modifications). A pseudo-category is a non strict version of an internal category. It was called a weak category and weak double category in some earlier papers. When internal to Cat it is at the same time a generalization of a bicategory and a double category.to be published in "Journal of Homotopy and Related Structures"Category TheoryRings and Algebrastext