Xiguang Li,  Existence of Solution for Boundary Value Problems of Differential Equations with Delay.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    August 2011, vol. 56(8). 1426 - 1428
    [viewed 18 April 2024]. Available from: https://publications.waset.org/pdf/7420.