“Existence and Ulam stability of first order nonsingular impulsive and delay integrodifferential system using a concept of the delayed matrix exponential”, Punjab Univ. J. Math., vol. 56, no. 6, pp. 252–274, Jun. 2024, Accessed: Jun. 28, 2025. [Online]. Available: https://pujm.pu.edu.pk/index.php/pujm/article/view/149