To cite package `Sojourn` in publications use:

  Paul R. Hibbing, Kate Lyden, & Isaac J. Schwabacher (2019). Sojourn:
  Apply Sojourn methods for processing ActiGraph accelerometer data.
  URL: https://github.com/paulhibbing/Sojourn.

A BibTeX entry for LaTeX users is

  @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://github.com/paulhibbing/Sojourn},
  }