M. Boukhrouk and  R. Ed-Dali,  Outbound Tourism in Developed Countries: Analysis of the Trends, Behavior and the Transformation of the Moroccan Demand for International Travels .   journal   = {International Journal of Social and Business Sciences}, [online]. World Academy of Science, Engineering and Technology.
    June 2018, vol. 139(7). 934 - 941
    [viewed 23 April 2024]. Available from: https://publications.waset.org/pdf/10009264.