Leila Nasiri,  Improved Triple Integral Inequalities of Hermite-Hadamard Type.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    July 2023, vol. 199(7). 61 - 68
    [viewed 28 April 2024]. Available from: https://publications.waset.org/pdf/10013156.