Review: Dual Electronics XGPS150A Bluetooth GPS – Takeoff Junkie
Field Review: Dual SkyPro XGPS160 GPS Receiver - OutdoorX4
Galileo Hits the Spot: Testing GNSS Dual Frequency with Smartphones - Inside GNSS - Global Navigation Satellite Systems Engineering, Policy, and Design
GPS Land Meter, Dual Satellite Positioning | ATO.com
Dual Electronics - Home Page
Topcon GPS 3D-MC2 Dual Antenna Dozer Kit w/ MC-R3 UHF II Control Box & GX-55 Display