Orestis Κ. Efthymiou and  Stavros T. Ponis,  Current Status of Industry 4.0 in Material Handling Automation and In-house Logistics.   journal   = {International Journal of Industrial and Manufacturing Engineering}, [online]. World Academy of Science, Engineering and Technology.
    September 2019, vol. 154(10). 1382 - 1386
    [viewed 17 January 2022]. Available from: https://publications.waset.org/pdf/10010833.