Aamir Mahmood Muhammad Ikram Ashraf Mikael Gidlund Johan Torsner Joachim Sachs Time Synchronization in 5G Wireless Edge: Requirements and Solutions for Critical-MTC. 45-51 2019 57 IEEE Commun. Mag. 12 https://doi.org/10.1109/MCOM.001.1900379 db/journals/cm/cm57.html#MahmoodAGTS19