To cite package 'fSRM' in publications use both:

Stas, L., Schönbrodt, D. F, Loeys, T. (2015). “ Getting the most out of family data with the R package fSRM.” Journal of Family Psychology, 29(2), 263–275. doi:10.1037/fam0000058.

Schönbrodt FD, Stas L, Loeys T (2021). fSRM: An R package for Social Relations Models with roles (version 0.6.5). https://cran.r-project.org/package=fSRM.

Corresponding BibTeX entries:

  @Article{,
    title = { Getting the most out of family data with the {R} package
      {fSRM}},
    volume = {29},
    doi = {10.1037/fam0000058},
    number = {2},
    journal = {Journal of Family Psychology},
    author = {{Stas} and {L.} and {Schönbrodt} and F. D. and {Loeys}
      and {T.}},
    year = {2015},
    pages = {263--275},
  }

  @Manual{,
    title = {{fSRM}: An {R} package for {S}ocial {R}elations {M}odels
      with roles (version 0.6.5)},
    author = {Felix D. Schönbrodt and Lara Stas and Tom Loeys},
    year = {2021},
    url = {https://cran.r-project.org/package=fSRM},
  }