“Chaotic Regions and Invariant Manifolds in Models for Elliptical Galaxies” (1987) Revista Mexicana de Astronomía y Astrofísica, 14(1), p. 80. Available at: https://astronomia.unam.mx/journals/rmxaa/article/view/1987rmxaa. 14. 80s (Accessed: 10 December 2025).