# Article

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Keywords:
perfect morphism; (pullback) closure operator; factorisation theory; orthogonal morphisms
Summary:
We define perfect morphisms to be those which are the pullback of their image under a given endofunctor. The interplay of these morphisms with other generalisations of perfect maps is investigated. In particular, closure operator theory is used to link closure and ortho\-go\-na\-lity properties of such morphisms. A number of detailed examples are given.
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