Please cite the underlying reference standard for whichever function(s)
you use, in addition to (or instead of) the pft package itself.

  Johnson P, Helgeson S (2026). _pft: Pulmonary Function Test
  Interpretation per ERS/ATS 2022_. R package version 1.0.1,
  <https://github.com/overdodactyl/pft>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {pft: Pulmonary Function Test Interpretation per ERS/ATS 2022},
    author = {Pat Johnson and Scott Helgeson},
    year = {2026},
    note = {R package version 1.0.1},
    url = {https://github.com/overdodactyl/pft},
  }

GLI 2012 spirometry equations (year = 2012):

  Quanjer P, Stanojevic S, Cole T, et al. (2012). “Multi-ethnic
  reference values for spirometry for the 3-95-yr age range: the global
  lung function 2012 equations.” _European Respiratory Journal_,
  *40*(6), 1324-1343. doi:10.1183/09031936.00080312
  <https://doi.org/10.1183/09031936.00080312>.

A BibTeX entry for LaTeX users is

  @Article{Quanjer2012,
    title = {Multi-ethnic reference values for spirometry for the 3-95-yr age range: the global lung function 2012 equations},
    author = {Philip H Quanjer and Sanja Stanojevic and Tim J Cole and {et al.}},
    journal = {European Respiratory Journal},
    year = {2012},
    volume = {40},
    number = {6},
    pages = {1324-1343},
    doi = {10.1183/09031936.00080312},
  }

GLI Global 2022 spirometry equations (year = 2022):

  Bowerman C, Bhakta N, Brazzale D, et al. (2023). “A race-neutral
  approach to the interpretation of lung function measurements.”
  _American Journal of Respiratory and Critical Care Medicine_,
  *207*(6), 768-774. doi:10.1164/rccm.202205-0963OC
  <https://doi.org/10.1164/rccm.202205-0963OC>.

A BibTeX entry for LaTeX users is

  @Article{Bowerman2023,
    title = {A race-neutral approach to the interpretation of lung function measurements},
    author = {Cole Bowerman and Nirav R Bhakta and Danielle Brazzale and {et al.}},
    journal = {American Journal of Respiratory and Critical Care Medicine},
    year = {2023},
    volume = {207},
    number = {6},
    pages = {768-774},
    doi = {10.1164/rccm.202205-0963OC},
  }

GLI 2021 static lung volumes (volume_normals):

  Hall G, Filipow N, Ruppel G, et al. (2021). “Official ERS technical
  standard: Global Lung Function Initiative reference values for static
  lung volumes in individuals of European ancestry.” _European
  Respiratory Journal_, *57*(3), 2000289.
  doi:10.1183/13993003.00289-2020
  <https://doi.org/10.1183/13993003.00289-2020>.

A BibTeX entry for LaTeX users is

  @Article{Hall2021,
    title = {Official ERS technical standard: Global Lung Function Initiative reference values for static lung volumes in individuals of European ancestry},
    author = {Graham L Hall and Nicole Filipow and Gregg Ruppel and {et al.}},
    journal = {European Respiratory Journal},
    year = {2021},
    volume = {57},
    number = {3},
    pages = {2000289},
    doi = {10.1183/13993003.00289-2020},
  }

GLI 2017 TLCO / DLCO (diffusion_normals). Author correction (2020),
doi:10.1183/13993003.50010-2017, is the version implemented here:

  Stanojevic S, Graham B, Cooper B, et al. (2017). “Official ERS
  technical standards: Global Lung Function Initiative reference values
  for the carbon monoxide transfer factor for Caucasians.” _European
  Respiratory Journal_, *50*(3), 1700010.
  doi:10.1183/13993003.00010-2017
  <https://doi.org/10.1183/13993003.00010-2017>.

A BibTeX entry for LaTeX users is

  @Article{Stanojevic2017,
    title = {Official ERS technical standards: Global Lung Function Initiative reference values for the carbon monoxide transfer factor for Caucasians},
    author = {Sanja Stanojevic and Brian L Graham and Brendan G Cooper and {et al.}},
    journal = {European Respiratory Journal},
    year = {2017},
    volume = {50},
    number = {3},
    pages = {1700010},
    doi = {10.1183/13993003.00010-2017},
  }

Pattern interpretation algorithm (ats_classification):

  Stanojevic S, Kaminsky D, Miller M, et al. (2022). “ERS/ATS technical
  standard on interpretive strategies for routine lung function tests.”
  _European Respiratory Journal_, *60*(1), 2101499.
  doi:10.1183/13993003.01499-2021
  <https://doi.org/10.1183/13993003.01499-2021>.

A BibTeX entry for LaTeX users is

  @Article{Stanojevic2022,
    title = {ERS/ATS technical standard on interpretive strategies for routine lung function tests},
    author = {Sanja Stanojevic and David A Kaminsky and Martin R Miller and {et al.}},
    journal = {European Respiratory Journal},
    year = {2022},
    volume = {60},
    number = {1},
    pages = {2101499},
    doi = {10.1183/13993003.01499-2021},
  }