To cite smacof in publications use:

de Leeuw J, Mair P (2009). “Multidimensional Scaling Using Majorization: SMACOF in R.” Journal of Statistical Software, 31(3), 1–30. https://www.jstatsoft.org/v31/i03/.

Corresponding BibTeX entry:

  @Article{,
    title = {Multidimensional Scaling Using Majorization: {SMACOF} in
      {R}},
    author = {Jan {de Leeuw} and Patrick Mair},
    journal = {Journal of Statistical Software},
    year = {2009},
    volume = {31},
    number = {3},
    pages = {1--30},
    url = {https://www.jstatsoft.org/v31/i03/},
  }