To cite package ‘phinterval’ in publications use:

  Sansom E (2026). _phinterval: Set Operations on Time Intervals_. R
  package version 1.0.0.9000,
  <https://github.com/ethansansom/phinterval>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {phinterval: Set Operations on Time Intervals},
    author = {Ethan Sansom},
    year = {2026},
    note = {R package version 1.0.0.9000},
    url = {https://github.com/ethansansom/phinterval},
  }