# Constructions of factorization systems in categories

@article{Bousfield1977ConstructionsOF, title={Constructions of factorization systems in categories}, author={Aldridge Knight Bousfield}, journal={Journal of Pure and Applied Algebra}, year={1977}, volume={9}, pages={207-220} }

In [2] we constructed homological localizations of spaces, groups, and 17"modules; here we generalize those constructions to give "factorization systems" and "homotopy factorization systems" for maps in categories. In Section 2 we recall the definition and basic properties of factorization systems, and in Section 3 we give our first existence theorem (3.1)for such systems. It can be viewed as a generalization of Deleanu's existence theorem [5] for localizations, and is best possible although it… Expand

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