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Eddie Silva, a staff sergeant select with the U.S. Marines, left, learns to use a trekker GPS device with John Kingston, right, an orientation and mobility specialist at the VA Western Blind
![Interface from an GPS navigator using the highway metaphor. Screen from... | Download Scientific Diagram Interface from an GPS navigator using the highway metaphor. Screen from... | Download Scientific Diagram](https://www.researchgate.net/publication/4085415/figure/fig5/AS:668922617548823@1536494988640/Interface-from-an-GPS-navigator-using-the-highway-metaphor-Screen-from-a-Silva-Multi.png)
Interface from an GPS navigator using the highway metaphor. Screen from... | Download Scientific Diagram
![NAVIGATION SKILLS FOR WALKERS - Map Reading, Compass and GPS (Pathfinder Guides): Terry Marsh: 9780319091753: Amazon.com: Books NAVIGATION SKILLS FOR WALKERS - Map Reading, Compass and GPS (Pathfinder Guides): Terry Marsh: 9780319091753: Amazon.com: Books](https://m.media-amazon.com/images/I/61B86e7XIhL._AC_UF350,350_QL50_.jpg)