Internal migration and mobile communication patterns among pairs with strong ties Mikaela Irene D. Fudolig, Daniel Monsivais, Kunal Bhattacharya, Hang-Hyun Jo and Kimmo Kaski EPJ Data Sci., 10 1 (2021) 16 Published online: 01 April 2021 DOI: 10.1140/epjds/s13688-021-00272-z