1. Andrews, D., Bruun, H., Hansen, B., Larsen, P., Plat, N. et al. 1995, Information Technology—Programming Languages, their environments and system software interfaces—Vienna Development Method-Specification Language Part I: Base language, ISO.
2. Barclays Bank PLC,. 1991, The Barclays code of business banking, Barclays Bank, Commercial Banking Division.
3. Bicarregui, J. C, Fitzgerald, J. S., Lindsay, P. A., Moore, R. and Ritchie, B. 1994, Proof in VDM: A Practitioner’s Guide, FACIT, Springer-Verlag.
4. Bowen, J. and Stavridou, V. 1992, Safety-critical systems, formal methods and standards, Technical Report PRG-TR-5-92, Oxford University Computing Laboratory.
5. Chung, L., Nixon, B. and Yu, E. 1995, Using non-functional requirements to systematically support change, RE’ 95 — Second IEEE international symposium on Requirements Engineering.