D. VIVEK; K. KANAGARAJAN; S. HARIKRISHNAN. Analytic Study on Nonlocal Initial Value Problems for Pantograph Equations with Hilfer-Hadamard Fractional Derivative. International Journal of Mathematics And its Applications, [S. l.], v. 6, n. 2 - A, p. 21–32, 2018. Disponível em: https://ijmaa.in/index.php/ijmaa/article/view/636. Acesso em: 3 jul. 2024.