Bouharket Bendouma, Amine Benaissa Cherif, and Ahmed Hammoudi. “Systems of First-Order Nabla Dynamic Equations on Time Scales”. Malaya Journal of Matematik 6, no. 04 (October 1, 2018): 757–765. Accessed December 4, 2024. https://www.malayajournal.org/index.php/mjm/article/view/924.