To cite package `Sojourn` in publications use:

Hibbing PR, Lyden K, Schwabacher IJ (2019). “Sojourn: Apply Sojourn methods for processing ActiGraph accelerometer data.” https://cran.r-project.org/package=Sojourn.

Corresponding BibTeX entry:

  @Misc{,
    title = {Sojourn: Apply Sojourn methods for processing ActiGraph
      accelerometer data},
    author = {Paul R. Hibbing and Kate Lyden and Isaac J. Schwabacher},
    year = {2019},
    url = {https://cran.r-project.org/package=Sojourn},
  }