Internet Radio Uniform Callsign - Standardised Internet Radio Call Letter Catalog System

Federal Register :: Revisions to Broadcast Auxiliary Service Rules

eCFR :: 47 CFR Part 15 -- Radio Frequency Devices

Approved Duty Identifier Patches and Tabs : r/AirForce

About Hoosier Heat Radio

Internet Radio FAQ National Association of Digital Broadcasters (NAdB)

Broadcast call signs - Wikipedia

FAQ: I currently own a call sign (with a -DB suffix) for my internet radio station, can I use that call sign on my LPFM station?

HD Radio - Wikipedia

The RAC Emergency Coordinator's Manual - Radio Amateurs of

Annual Safety Recommendations Review 2011 - European Aviation