To cite RAppArmor in publications use:

  Ooms J (2013). “The RAppArmor Package: Enforcing Security Policies in
  R Using Dynamic Sandboxing on Linux.” _Journal of Statistical
  Software_, *55*(7), 1-34. <https://www.jstatsoft.org/v55/i07/>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {The {RAppArmor} Package: Enforcing Security Policies in {R} Using Dynamic Sandboxing on Linux},
    author = {Jeroen Ooms},
    journal = {Journal of Statistical Software},
    year = {2013},
    volume = {55},
    number = {7},
    pages = {1--34},
    url = {https://www.jstatsoft.org/v55/i07/},
  }