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 Elementary Topology: A First Course Viro, Ivanov, Netsvetaev, Kharlamov (St. Petersburg University)
 An invitation to Topology Planar Machines' web site
 Geometry and Topology Index , MacTutor History of Mathematics archive 
 ODP category
 The Topological Zoo at The Geometry Center
 Topology Atlas
 Topology Course Lecture Notes Aisling McCluskey and Brian McMaster, Topology Atlas
 Topology Glossary 
 Rigorous proof of a discrete space's countability 
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