WASET
    Walter Sebron and  Hans Tschürtz and  Peter Krebs,  VISMA: A Method for System Analysis in Early Lifecycle Phases.   journal   = {International Journal of Industrial and Manufacturing Engineering}, [online]. World Academy of Science, Engineering and Technology.
    February 2017, vol. 123(3). 661 - 671
    [viewed 24 April 2024]. Available from: https://publications.waset.org/pdf/10006743.