References ~~~~~~~~~~ Heath, R.W., Screenability, pointwise para- compactness, and metrization of Moore spaces. Canadian J. Mathem. 16 (1964), pp. 763-770. Johnstone, P.T., Linton, F.E.J. and Paré, R., Injectives in Topoi, II: Connections with the Axiom of Choice. In: Categorical Topology, Proceedings, Berlin, 1978; Springer LNM 719, 1979, pp. 207-216.
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