WASET
    Fateme Ashari-Ghomi and  Najme Khorasani and  Abbas Nowzari-Dalini,  Ranking and Unranking Algorithms for k-ary Trees in Gray Code Order.   journal   = {International Journal of Computer and Information Engineering}, [online]. World Academy of Science, Engineering and Technology.
    August 2012, vol. 68(8). 1020 - 1025
    [viewed 27 April 2024]. Available from: https://publications.waset.org/pdf/9384.