A fascinating aspect of computer science is its variety of application domains. Sometimes the solution to a problem involving one application domain can be extended to a wide variety of domains. (A good example is the C programming language, intended originally for the creation of operating systems, but which has since been successfully used in many other areas.) Similarly, this paper describes a framework (X3ML) that is needed for the aggregation of heterogeneous data from different institutions in cultural heritage and e-science, but has also had significant impact elsewhere. This framework, based on the X3ML mapping definition language, handles schema mapping, uniform resource identifier (URI) definition and generation, and other aspects of information integration. The paper describes both the X3ML architecture and usability aspects of this framework.

Related work, which covers much of the more than 60 references, is discussed and organized in a nice table. A separate section is devoted to the X3ML mapping definition language. Then, the framework itself is described with the help of several good examples, as well as a set of figures. Finally, performance metrics are introduced and used for evaluation of the framework.

This paper can be useful to both researchers of object-oriented database development (including graduate students), and for information technology (IT) staff of institutions that might benefit from the use of a database with an X3ML framework.