Armend Sh. Shabani,  The Proof of Two Conjectures Related to Pell-s Equation x2 −Dy2 = ± 4.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    July 2008, vol. 19(7). 443 - 446
    [viewed 20 April 2024]. Available from: https://publications.waset.org/pdf/14954.