Noulas, A., S. Scellato, C. Mascolo, and M. Pontil. “An Empirical Study of Geographic User Activity Patterns in Foursquare”. Proceedings of the International AAAI Conference on Web and Social Media, vol. 5, no. 1, Aug. 2021, pp. 570-3, https://ojs.aaai.org/index.php/ICWSM/article/view/14175.