Dieter Fensel, Ontologies: a Silver Bullet for Knowledge Management and Electronic Commerce, Springer, 1998

A hyperbolic presentation of the ontology and a tabular interface improve the accessibility of Ontobroker.... a user needs an overview of the entire hierarcy to allow for a quick and easy navigation from one class in the hierarchy to another class. These requirements are met by a presentation scheme based on Hyperbolic Geometry [Lamping et al., 1995], where classes in the center are depicted with a large circle and classes at the border of the surrounding circle are only marked with a small circle (see Figure [at right]).