To cite FitARMA in publications use:

A. I. McLeod, Ying Zhang (2007). Faster ARMA maximum likelihood estimation Computational Statistics & Data Analysis 52(4) URL http://dx.doi.org/10.1016/j.csda.2007.07.020

Corresponding BibTeX entry:

  @Article{,
    title = {Faster ARMA maximum likelihood estimation},
    author = {A. I. McLeod and Ying Zhang},
    journal = {Computational Statistics & Data Analysis},
    year = {2007},
    volume = {52},
    number = {4},
    pages = {2166-2176},
    url = {http://dx.doi.org/10.1016/j.csda.2007.07.020},
  }