GF_MBY_CESA_jul_2003
 Bani Younis, M.; Frey, G.:
Formalization of Existing PLC Programs: A Survey.
 Proceedings of CESA 2003, Lille (France), Paper No. S2-R-00-0239, July  2003. 
-  In recent years, the interest in the formalization of PLC programs  increased. The paper provides a clas-sification scheme for the works done in this  field. This scheme includes the sources used for formaliza-tion, the level of  the formalization process (i.e. the complexity of structures that could be  handled by the approach), the aim of the formalization (Re-Engineering or  Verification) and the formal model used to represent the formalized PLC program. The  scheme is applied to several examples. 
