BOOYSEN, A. . On Second-Order Asymptotic Expansions at a Caustic. Applied Computational Electromagnetics Society Journal (ACES), [S. l.], v. 20, n. 1, p. 21–34, 2022. Disponível em: https://journals.riverpublishers.com/index.php/ACES/article/view/16563. Acesso em: 13 may. 2026.