References
[Gent and Walsh, 1993]
Gent, Ian P. and Walsh, Toby. An empirical analysis of search in GSAT. 1993. <URL:http://ic-www.arc.nasa.gov/ic/jair-www/volume1/gent93a.ps>.
Cyberspace geography visualization - 15 October 1995
Luc Girardin, The Graduate Institute of International Studies