WASET
    Khidir R. Sharaf and  Didar A. Ali,  Nullity of t-Tupple Graphs.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    January 2014, vol. 86(2). 314 - 324
    [viewed 26 April 2024]. Available from: https://publications.waset.org/pdf/9997480.