1. Common Language Location Identifier (CLLI) code. http://en.wikipedia.org/wiki/CLLI_code. Common Language Location Identifier (CLLI) code. http://en.wikipedia.org/wiki/CLLI_code.
2. NetAcuity. http://www.digitalelement.com/our_technology/our_technology.html. NetAcuity. http://www.digitalelement.com/our_technology/our_technology.html.
3. PeeringDB. http://www.peeringdb.com. PeeringDB. http://www.peeringdb.com.
4. RIPE RIS. http://www.ripe.net/ris. RIPE RIS. http://www.ripe.net/ris.
5. Route\uppercaseviews. http://www.routeviews.org/. Route\uppercaseviews. http://www.routeviews.org/.