Voir la notice de l'article provenant de la source Theory and Applications of Categories website
Codescent morphisms are described in regular categories which satisfy the so-called strong amalgamation property. Among varieties of universal algebras possessing this property are, as is known, categories of groups, not necessarily associative rings, M-sets (for a monoid M), Lie algebras (over a field), quasi-groups, commutative quasi-groups, Steiner quasi-groups, medial quasi-groups, semilattice$lattices, weakly associative lattices, Boolean algebras, Heyting algebras. It is shown that every codescent morphism of groups is effective.
@article{TAC_2003_11_a19, author = {Dali Zangurashvili}, title = {The strong amalgamation property and (effective) codescent morphisms}, journal = {Theory and applications of categories}, pages = {438--449}, publisher = {mathdoc}, volume = {11}, year = {2003}, language = {en}, url = {http://geodesic.mathdoc.fr/item/TAC_2003_11_a19/} }
Dali Zangurashvili. The strong amalgamation property and (effective) codescent morphisms. Theory and applications of categories, Tome 11 (2003), pp. 438-449. http://geodesic.mathdoc.fr/item/TAC_2003_11_a19/