PRASAD, Ashish Kumar; SINGH, Anant Pratap; KHATRI, Sony. Duality for a class of second order symmetric nondifferentiable fractional variational problems. Yugoslav Journal of Operations Research, [S. l.], v. 30, n. 2, p. 121–136, 2020. DOI: 10.2298/YJOR190215004P. Disponível em: https://yujor.erc.fon.bg.ac.rs/index.php/yujor/article/view/614. Acesso em: 29 jan. 2026.