On the Lambek Invariants of Commutative Squares in a Quasi-Abelian Category

2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/95434We consider the invariants Ker and Im for commutative squares in quasi-abelian categories. These invariants were introduced by Lambek for groups and then studied by Hilton and Nomura in exact categories.10 pagesCategory TheoryFunctional Analysis18A20, 46M99On the Lambek Invariants of Commutative Squares in a Quasi-Abelian Categorytext