# PlanetPhysics/C2 Category

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In general, a-categoryis an -category, or, alternatively, an - and -category with certain additional conditions for the canonical morphism from direct sums to products of any family of objects in^{[1]}).

A *-category* is defined as a category that has products, coproducts and a zero object, and if the morphism is a monomorphism for any family of objects in (p. 81 in ^{[2]}).

One readily obtains the result that a -category is (^{[2]}).

## All SourcesEdit

^{[2]}^{[1]}

## ReferencesEdit

- ↑
^{1.0}^{1.1}Ref. in the Bibliography for categories and algebraic topology - ↑
^{2.0}^{2.1}^{2.2}Ref. in the Bibliography for categories and algebraic topology