TIGAN, Gheorghe. SUBCRITICAL HOPF BIFURCATION INGEORGE SYSTEM. Matematichki Bilten, [S. l.], v. 28, n. 1, p. 81–90, 2004. Disponível em: https://bilten.smm.org.mk/index.php/bilten/article/view/1701. Acesso em: 14 aug. 2026.