ASWATHBABU.O.G, GOPINATH.P, RAJKUMAR.S, and S.KAVITHA. “Velocity Based Tracking and Localization System Using Smartphones With GPS and GPRS/3G”. International Journal of Intellectual Advancements and Research in Engineering Computations, vol. 6, no. 2, Mar. 2018, pp. 1853-7, https://ijiarec.com/ijiarec/article/view/747.