Building an object-oriented model requires knowledge of process and techniques. Representing the model itself requires the use of a notation underpinned by a rigorous definition. Today this underpinning usually starts with a metamodel. Together, the metamodel and the notation are known as a "modelling language". Two modelling languages are described, discussed and compared: OML (the OPEN Modelling Language) and UML (the Unified Modeling Language). Advanced use of both languages is described particularly for concepts such as roles, for stereotypes and for aggregations, associations and other relationships.
['Brian Henderson-Sellers']
Advanced 00 Modelling: Metamodels and Notations for the Next Millenium