References
[Ultsch and Vetter, 1994]
Ultsch, Alfred; Vetter, C. Self-organizing-feature-maps versus statistical clustering methods: a benchmark. 1994. <URL:http://www.mathematik.uni-marburg.de/~wina/papers/94.cluster.ps>
Cyberspace geography visualization - 15 October 1995
Luc Girardin, The Graduate Institute of International Studies