  As more data-intensive applications emerge, advanced retrieval semantics,
such as ranking or skylines, have attracted attention. Geographic information
systems are such an application with massive spatial data. Our goal is to
efficiently support skyline queries over massive spatial data. To achieve this
goal, we first observe that the best known algorithm VS2, despite its claim,
may fail to deliver correct results. In contrast, we present a simple and
efficient algorithm that computes the correct results. To validate the
effectiveness and efficiency of our algorithm, we provide an extensive
empirical comparison of our algorithm and VS2 in several aspects.
