TY - RPRT TI - Characterizing the dependence of satellite-based augmentation systems upon the spatial distribution of GPS measurements AU - Sparks, L. AU - Komjathy, A. AU - Mannucci, A. J. AU - Pi, X. PY - 2003 UR - https://ntrs.nasa.gov/citations/20060040021 ID - 20060040021 ER -