1. Proceedings of First International Advanced Study Symposium on Topological Data Structures for Geographic Information Systems,1978
2. Geographic data processing;Nagy;ACM Comput. Surv.,1979
3. Map Data Processing,1980
4. Computing Dirichlet tesselations in the plane;Green;Comput. J.,1977
5. A topological data structure for multi-element map processing;Brassel,1978