Instantaneous, Dual-Frequency, Multi-GNSS Precise RTK Positioning Using Google Pixel 4 and Samsung Galaxy S20 Smartphones for Zero and Short Baselines. - Chien Zheng Yong; Robert Odolinski; Safoora Zaminpardaz; Michael Moore; Eldar Rubinov; Jeremiah Er; Mike Denham (Sensors, 2021)