To cite robustbase in publications use:

To cite package ‘robustbase’ in publications use:

  Martin Maechler, Peter Rousseeuw, Christophe Croux, Valentin Todorov,
  Andreas Ruckstuhl, Matias Salibian-Barrera, Tobias Verbeke, Manuel
  Koller, c("Eduardo", "L. T.") Conceicao and Maria Anna di Palma
  (2024). robustbase: Basic Robust Statistics R package version
  0.99-4-1. URL http://CRAN.R-project.org/package=robustbase

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {robustbase: Basic Robust Statistics},
    author = {Martin Maechler and Peter Rousseeuw and Christophe Croux and Valentin Todorov and Andreas Ruckstuhl and Matias Salibian-Barrera and Tobias Verbeke and Manuel Koller and Eduardo L. T. Conceicao and Maria {Anna di Palma}},
    year = {2024},
    note = {R package version 0.99-4-1},
    url = {http://robustbase.r-forge.r-project.org/},
    url = {http://robustbase.r-forge.r-project.org/},
  }

To cite the multivariate class/methods framework use:

  Valentin Todorov, Peter Filzmoser (2009). An Object-Oriented
  Framework for Robust Multivariate Analysis. Journal of Statistical
  Software, 32(3), 1-47. URL
  https://www.jstatsoft.org/article/view/v032i03/.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {An Object-Oriented Framework for Robust Multivariate Analysis},
    author = {Valentin Todorov and Peter Filzmoser},
    journal = {Journal of Statistical Software},
    year = {2009},
    volume = {32},
    number = {3},
    pages = {1--47},
    url = {https://www.jstatsoft.org/article/view/v032i03/},
  }