TY  - BOOK
AU  - French, Gregory T.
TI  - Understanding the GPS: : an introduction to the global positioning system : what it is and how it works
SN  - 0-9655723-O-7
PY  - 1996///
CY  - Bethesda
PB  - : GeoResearch
KW  - GPS (Sistema de Posicionamiento Global)
ER  -