B. D. Ghimire, N. P. Chapagain, V. Basnet, and B. Khadka, “Analysis of Tec Variations over Nepal Obtained from GPS Data on Geo-Magnetically Quiet and Disturbed Days of the Year 2015”, J. Nep. Phys. Soc., vol. 7, no. 2, pp. 102–109, Aug. 2021.