The Alexandroff Duplicate and its subspaces


  • Agata Caserta Seconda Università degli Studi di Napoli
  • Stephen Watson York University



Resolution, Alexandroff duplicate, Lindelöf property, Michaeltype line


We study some topological properties of the class of the Alexandroff duplicates and their subspaces. We give a characterization of metrizability and Lindel¨of properties of subspaces of the Alexandroff duplicate. This characterization clarifies the potential for finding Michael spaces among the subspaces of Alexandroff duplicates.


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Author Biographies

Agata Caserta, Seconda Università degli Studi di Napoli

Dipartimento di Matematica

Stephen Watson, York University

Department of Mathematics and Statistics


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How to Cite

A. Caserta and S. Watson, “The Alexandroff Duplicate and its subspaces”, Appl. Gen. Topol., vol. 8, no. 2, pp. 187–205, Oct. 2007.