1. Barras et al. (1997), The Coq Proof Assistant Reference Manual: Version 6.1. Technical Report, INRIA, Roquencourt, France. See also “The Coq WWWeb Page” http://www.inria.fr/Equipes/COQ-eng.html.
2. Bornat, R. and B. Sufrin (1998), Jape — A Framework for building Interactive Proof Editors. See http://www.comlab.ox.ac.uk/oucl/users/bernard.sufrin/jape.html.
3. Burstall, R. (1994), Terms, Proofs and Refinements. (Extended abstract) LICS94, Springer-Verlag.
4. Burstall, R. (1998), WWW Home page, See http://www.dcs.ed.ac.uk/home/rb/.
5. Dyckhoff, R. et al. (1998), MacLogic WWW Home Page, See http://www-theory.dcs.st-and.ac.uk/"rd/logic/intro.html.