To cite MST in publications use:

Calhoun P, Su X, Nunn M, Fan J (2018). “Constructing Multivariate Survival Trees: The MST Package for R.” Journal of Statistical Software, 83(12), 1–21. doi: 10.18637/jss.v083.i12.

Corresponding BibTeX entry:

  @Article{,
    title = {Constructing Multivariate Survival Trees: The {MST}
      Package for {R}},
    author = {Peter Calhoun and Xiaogang Su and Martha Nunn and
      Juanjuan Fan},
    journal = {Journal of Statistical Software},
    year = {2018},
    volume = {83},
    number = {12},
    pages = {1--21},
    doi = {10.18637/jss.v083.i12},
  }