1. Gul Agha and Carl Hewitt. Actors: A conceptual foundation for concurrent object-oriented programming. In P. Wegner and B. Shriver, editors, Research Directions in Object-Oriented Programming, pages 49–74. MIT Press, 1987.
2. P. S. Almeida. Control of Object Sharing (provisional title). PhD thesis, University of London, Imperial College, Department of Computing, 1997. To appear.
3. G. E. Andrews. The theory of partitions. In Encyclopedia of Mathematics and its Applications, volume 2. Addison-Wesley, 1976.
4. K. Arnold and J. Gosling. The Java Programming Language. Addison-Wesley, 1996.
5. Franco Civello. Roles for composite objects in object-oriented analysis and design. Proceedings OOPSLA'93. SIGPLAN Notices, 28(10):376–393, October 1993.