1. D.G. Bobrow, K. Kahn, G. Kiczales, L. Masinter, M. Stefik, F. Zdybel, CommonLoops: Merging Lisp and object-oriented programming, in: N. Meyrowitz (Ed), Proceedings of the Conference on Object-Oriented Programming, Systems, Languages, and Applications, OOPSLA, Portland, OR, November 1986, pp. 17–29
2. Compound types for Java;Büchi,1998
3. L. Cardelli, Typeful programming, SRC Research Report 45, Digital Systems Research Center, 130 Lytton Avenue, Palo Alto, CA 94301, May 24, 1989
4. On understanding types, data abstraction, and polymorphism;Cardelli;ACM Computing Surveys,1985
5. C. Chambers, The Cecil language: specification and rationale, Technical Report, Department of Computer Science and Engineering, University of Washington, Box 352350, Seattle, WA 98195-2350, USA, March 1997, Available at http://www.cs.washington.edu/research/projects/cecil/