...$neighbors$ ¹

In a not-so-academic wording, your nearest neighbor is an object that is closest to you and your reverse nearest neighbor is any object for which you are the closest object.

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... $surrounders$ ²

Your nearest surrounders are the objects that are nearest to you and surround you completely.

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... queries³

This work was partially supported by the Australian Research Council (ARC) Discovery Grant (DP0666428)

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... accessed.⁴

The case when query $q$ reports location update and is treated as new query is exception to this claim.

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