1. ClearSy, http://www.atelierb.societe.com/index.html
2. B-Core http://www.b-core.com/btoolkit.html
3. M. Abadi and L. Lamport, The existence of refinement mappings, Technical Report. Digital Systems Research Center, Palo Alto, California, 1988.
4. The B Book. Assigning programs to Meanings;Abrial,1996
5. Abrial J.R., Extending B without changing it, for Developing Distributed System, in First B conference, H. Habrias editor, 169–190, Nantes, 1996.