To cite the SGP package in publications use:

Damian W. Betebenner, Adam R. Van Iwaarden, Benjamin Domingue and Yi Shang (2026). SGP: Student Growth Percentiles & Percentile Growth Trajectories. (R package version 2.2-3.1) URL: https://sgp.io

Corresponding BibTeX entry:

  @Manual{,
    title = {{SGP}: Student Growth Percentiles \& Percentile Growth
      Trajectories.},
    author = {Damian W. Betebenner and Adam R. {Van Iwaarden} and
      Benjamin Domingue and Yi Shang},
    year = {2026},
    note = {R package version 2.2-3.1},
    url = {https://sgp.io},
  }