Andreas Ahrens and  Ojaras Purvinis Jelena Zāšcerinska,  Decomposition of the Customer-Server Interaction in Grocery Shops.   journal   = {International Journal of Economics and Management Engineering}, [online]. World Academy of Science, Engineering and Technology.
    December 2022, vol. 192(12). 836 - 840
    [viewed 23 April 2024]. Available from: https://publications.waset.org/pdf/10012853.