1. Akmaev , R. A. A. Newman M. Codrescu C. Schulz E. Nerney 2010 D-RAP model validation: I. Scientific report https://www.ngdc.noaa.gov/stp/drap/DRAP-V-Report1.pdf
2. A new magnetic coordinate system for conjugate studies at high latitudes;Baker;J. Geophys. Res.,1989
3. Bhavnani , K. H. C. A. Hein 1994 An improved algorithm for computing altitude dependent corrected geomagnetic coordinates Tech Rep PL-TR-94-2310
4. An imaging riometer for ionospheric studies;Browne;Electron. Commun. Eng. J.,1995