http://www.titantv.com
2. PBS Digital TV
http://www.pbs.org
3. ATTC
http://www.attc.org
4. Digital Television
http://www.digitaltelevision.com
5. DigitalBroadcasting.com
http://www.digitalbroadcasting.com
6. ATSC
http://www.atsc.org
7. FCC
http://www.fcc.gov
8. DVB
http://www.dvb.org
9. Omnilan
http://www.omnilan.com