BUDAK, Hüseyin; SARIKAJA, Mehmet Zeki. An inequality of Ostrowski-Grüss type for double integrals. Studia Universitatis Babeș-Bolyai Mathematica, [S. l.], v. 62, n. 2, p. 163–173, 2017. DOI: 10.24193/subbmath.2017.2.03. Disponível em: https://studia.reviste.ubbcluj.ro/index.php/subbmathematica/article/view/1771. Acesso em: 5 feb. 2025.