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2. Herrlich, H.: Topologische Reflexionen und Coreflexionen. Lecture Notes 78. Berlin-Heidelberg-New York: Springer.
3. -- Strecker, G. E.: Coreflective subcategories I. Generealities (to appear).
4. -- -- Coreflective subcategories II. Applications in general topology (to appear).
5. Kennison, J. F.: Reflective functors in general topology and elsewhere. Trans. Amer. Math. Soc.118, 303?315 (1965).