To cite package ‘sem’ in publications use:

  Fox J, Nie Z, Byrnes J (2024). _sem: Structural Equation Models_. R
  package version 3.1-16, <https://CRAN.R-project.org/package=sem>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {sem: Structural Equation Models},
    author = {John Fox and Zhenghua Nie and Jarrett Byrnes},
    year = {2024},
    note = {R package version 3.1-16},
    url = {https://CRAN.R-project.org/package=sem},
  }