To cite mnlogit in publications use:

Asad Hasan, Zhiyu Wang, Alireza S. Mahani (2016). Fast Estimation of Multinomial Logit Models: R Package mnlogit. Journal of Statistical Software, 75(3), 1-24.<doi:10.18637/jss.v075.i03>

Corresponding BibTeX entry:

  @Article{,
    title = {Fast Estimation of Multinomial Logit Models: {R} Package
      {mnlogit}},
    author = {Asad Hasan and Zhiyu Wang and Alireza S. Mahani},
    journal = {Journal of Statistical Software},
    year = {2016},
    volume = {75},
    number = {3},
    pages = {1--24},
    doi = {10.18637/jss.v075.i03},
  }