José Luis Castro Quilantán., José Luis del Río-Correa., . and Marco Antonio Rosales Medina. (1995) “Alternative proof of Bertrand’s theorem using a phase space approach”, Revista Mexicana de Física, 42(5), pp. 867–877. Available at: https://rmf.smf.mx/ojs/index.php/rmf/article/view/2622 (Accessed: 5 July 2024).