1[1]Andrew Cullison and Ruth Johnsen: Technology Showcased at the 1999 ASW Exposition, 1999, 78,43.
2[2]Richard Zurawski and Meng Chu Zhou: IEEE Trans. On IE, 1994, 40, 567.
3[3]M.Ozam and A.H.Jones: Int. J. Adv. Manuf. Technol., 1998, 14, 716.
4Dr M. Uzam,A. H. Jones.Discrete event control system design using automation Petri nets and their ladder diagram implementation[J].The International Journal of Advanced Manufacturing Technology.1998(10)