A non-simultaneous variational approach for the oscillators with fractional-order power nonlinearities. - Ivana Kovacic; Zvonko Rakaric; Livija Cveticanin (Appl. Math. Comput., 2010)

Asymptotic methods for vibrations of the pure non-integer order oscillator. - Livija Cveticanin; Ivana Kovacic; Zvonko Rakaric (Comput. Math. Appl., 2010)

An elliptic averaging method for harmonically excited oscillators with a purely non-linear non-negative real-power restoring force. - Zvonko Rakaric; Ivana Kovacic (Commun. Nonlinear Sci. Numer. Simul., 2013)