“…Among the aforementioned routes to chaos, cascaded period-doubling bifurcations to chaos constitute a familiar scenario which has been studied extensively. Many methods, including the method of multiple scales [2,3], numerical time-integration [4][5][6][7][8][9], shooting method [10][11][12][13], the incremental harmonic balance (IHB) method [14][15][16][17][18][19], and the experimental method [20], etc., have been developed and applied to predict period-doubling bifurcations.…”