Roukema, B. F.2012-03-122012-03-122000-03-25http://hdl.handle.net/11007/1282Many diļ¬erent and complementary strategies for translating the basic principle of multiple topological imaging into observational analysis are now available, both for three-dimensional and two-dimensional catalogues.enTopology: universeObservational cosmic topologyObservational Approaches to the topology of the universePreprint