http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
boatowner's guide to GMDSS and marine radio
Marine distress and safety communications in the digital age
The new digital Global Maritime Distress and Safety System (GMDSS) is revolutionizing emergency communications and international search-and-rescue at sea. Clearly and concisely, this one-of-a-kind guide presents what you should know about using digital marine radios for emergency assistance and enhanced safety.
Radio in navigation,Artificial satellites in navigation,Navigation,Distress signals