1. https://yhongcs.github.io/pub/ccs22.pdf https://yhongcs.github.io/pub/ccs22.pdf
2. https://www.apple.com/privacy/docs/Differential_Privacy_Overview.pdf https://www.apple.com/privacy/docs/Differential_Privacy_Overview.pdf
3. https://docs.microsoft.com/en-us/bingmaps/articles/bing-maps-tile-system https://docs.microsoft.com/en-us/bingmaps/articles/bing-maps-tile-system
4. http://snap.stanford.edu/data/loc-gowalla.html http://snap.stanford.edu/data/loc-gowalla.html
5. M. Andrés , N. Bordenabe , K. Chatzikokolakis , and C. Palamidessi . Geoindistinguishability: Differential privacy for location-based systems . In Computer and Communications Security , pages 901 -- 914 , 2013 . M. Andrés, N. Bordenabe, K. Chatzikokolakis, and C. Palamidessi. Geoindistinguishability: Differential privacy for location-based systems. In Computer and Communications Security, pages 901--914, 2013.