Raymarine manuals: http://www.raymarine.com/view/?id=5694

Garmin manuals: https://support.garmin.com/support/manuals/searchManuals.faces

Simrad and Lowrance manuals: http://www.navico-commercial.com/en-US/Support/Downloads/Manuals-and-Literature/

Rescue 21 System Overview: http://wow.uscgaux.info/content.php?unit=170&category=dsc-vhf-radio-rescue-21

Register for an MMSI direct from the FCC: https://www.fcc.gov/wireless/bureau-divisions/mobility-division/ship-radio-stations

Register for an MMSI from BoatUS: http://www.boatus.com/MMSI

Register for an MMSI from SeaTow: https://www.seatow.com/tools-and-education/mmsi

EPIRB System Overview: http://coastguard.dodlive.mil/2011/05/whats-an-epirb/

Register Your EPIRB: https://beaconregistration.noaa.gov