Alur, Rajeev, and Thomas A Henzinger. “Real-Time Logics: Complexity and Expressiveness.”https://doi.org/10.1006/inco.1993.1025__Information and Computation. Elsevier, 1993.https://doi.org/10.1006/inco.1993.1025 .

Edelsbrunner, Herbert, and Franco Preparata. “Minimum Polygonal Separation.”https://doi.org/10.1016/0890-5401(88)90049-1__Information and Computation. Elsevier, 1988.https://doi.org/10.1016/0890-5401(88)90049-1 .