Previously the torsion number and the relative torsion number have been introduced to describe the topological character of periodic solutions of a three-dimensional ordinary differential equation. In this letter, considering the rewinding mechanism of tangent vectors, we investigate the change of the torsion numbers and the relative torsion numbers as period-doubling bifurcation cascades. © 1983.
Uezu, T. (1983). Topology in dynamical systems. Physics Letters A, 93(4), 161–166. https://doi.org/10.1016/0375-9601(83)90038-5