Richardson Extrapolation and Defect Correction of Finite Element Methods for Optimal Control Problems. Journal of Computational Mathematics, [S. l.], v. 28, n. 1, p. 55–71, 2018. DOI: 10.4208/jcm.2009.09-m1001. Disponível em: https://www.global-sci.com/index.php/JCM/article/view/11973. Acesso em: 5 dec. 2025.