1. ARMC. http://www.mpi-sb.mpg.de/~rybal/armc/ . Accessed 30 June 2010
2. ASPIC. http://laure.gonnord.org/pro/aspic/aspic.html . Accessed 30 June 2010
3. L2CA. http://www-verimag.imag.fr/~async/L2CA/l2ca.html . Accessed 30 June 2010
4. Smallfoot. http://www.dcs.qmul.ac.uk/research/logic/theory/projects/smallfoot/index.html . Accessed 30 June 2010
5. LNCS;A Annichini,2001