@article{
  author = {Ayazi, Amir, Khah, Hadi Ebrahimi},
  title = {Determination of the amplitude-frequency for strongly nonlinear oscillator by two approximate analytical techniques},
  journal = {Journal of Theoretical and Applied Physics},
  year = {2013},
  volume = {0},
  number = {1},
  pages = {0-0},
  doi = {10.1186/2251-7235-7-38}
}