Marie Mikušová and  Petr Šnapka and  Viktorie Janečková,  The Elements of the Crisis Concept.   journal   = {International Journal of Economics and Management Engineering}, [online]. World Academy of Science, Engineering and Technology.
    November 2011, vol. 59(11). 1531 - 1535
    [viewed 21 September 2020]. Available from: https://publications.waset.org/pdf/7842.