shttp:// http://www.ncbinlmnihgov/ Entrezhttp://www.ncbi.nlmnihgov/entrez/ VirtualTouristhttp://www.vtourist.com/webmap/ AngiShttp://www.angis.su.oz.au/ CityNethttp://www.city.netSRS http://srs.ebi.ac.uk/ NCBI http://www.ncbi.nlm.nih.gov/ Entrez http://www.ncbi.nlm.nih.gov/Entrez/ Virtual Tourist http://www.vtourist.com/webmap/ ANGIS http://www.angis.su.oz.au/ City.Net http://www.city.net/