1. Matlab help page for “Standard Deviation” (Std) function MathWorks https://www.mathworks.com/help/matlab/ref/std.html
2. Global Positioning System Wide Area Augmentation System (WAAS) Performance Standard (U.S. Federal Aviation Administration Washington DC) 1st Ed. October 31 2008.
3. Minimum Aviation System Performance Standards for the Local Area Augmentation System (LAAS) Washington DC RTCA SC‐159 WG‐4 DO‐245A December 9 2004.