U.K. Saha and  L.K. Arora,  Riemann-Liouville Fractional Calculus and Multiindex Dzrbashjan-Gelfond-Leontiev Differentiation and Integration with Multiindex Mittag-Leffler Function.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    August 2010, vol. 44(8). 1120 - 1124
    [viewed 27 January 2020]. Available from: https://publications.waset.org/pdf/15470.