1. Armenatzoglou, N., Papadopoulos, S., Papadias, D.: A general framework for geo-social query processing. PVLDB 6(10), 913–924 (2013)
2. Bahmani, B., Goel, A.: Partitioned multi-indexing: bringing order to social search. In: WWW 2012, pp. 399–408. ACM, New York (2012)
3. Busch, M., Gade, K., Larson, B., Lok, P., Luckenbill, S., Lin, J.: Earlybird: real-time search at Twitter. In: ICDE 2012, pp. 1360–1369 (2012)
4. Cong, G., Jensen, C.S., Wu, D.: Efficient retrieval of the top-k most relevant spatial web objects. PVLDB 2(1), 337–348 (2009)
5. Curtiss, M., Becker, I., et al.: Unicorn: a system for searching the social graph. PVLDB 6(11), 1150–1161 (2013)