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

Yaroslav Kopylov
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Abstract

We 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.

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Yaroslav Kopylov. 2005-10-04. On the Lambek Invariants of Commutative Squares in a Quasi-Abelian Category. https://arxiv.org/abs/math/0510072

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