WASET
    Mamoun Sqali and  Mohamed Wassim Trojet,  Multi-models Approach for Describing and Verifying Constraints Based Interactive Systems.   journal   = {International Journal of Electrical and Computer Engineering}, [online]. World Academy of Science, Engineering and Technology.
    May 2009, vol. 29(5). 1315 - 1325
    [viewed 25 April 2024]. Available from: https://publications.waset.org/pdf/3311.