Ahmet Tekcan,  The Pell Equation x2 − (k2 − k)y2 = 2t.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    July 2008, vol. 19(7). 424 - 428
    [viewed 11 April 2021]. Available from: https://publications.waset.org/pdf/7073.