To cite the 'STARTS' package in publications use:

  Robitzsch, A., & Luedtke, O. (2022). STARTS: Functions for the STARTS
  Model. R package version 1.3-8.
  https://CRAN.R-project.org/package=STARTS

A BibTeX entry for LaTeX users is

  @Manual{starts_R package version 1.3-8,
    title = {STARTS: Functions for the STARTS Model},
    author = {Alexander Robitzsch and Oliver Luedtke},
    year = {2022},
    note = {R package version 1.3-8},
    url = {https://CRAN.R-project.org/package=STARTS},
  }