Adam Czornik and  Aleksander Nawrat,  Stability of Discrete Linear Systems with Periodic Coefficients under Parametric Perturbations.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    March 2011, vol. 51(3). 206 - 209
    [viewed 11 May 2024]. Available from: https://publications.waset.org/pdf/14593.