To cite aqp in publications use:

  Beaudette, D., Roudier, P., Brown, A. (2023). aqp: Algorithms for
  Quantitative Pedology. R package version 2.0.
  <https://CRAN.R-project.org/package=aqp>

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {aqp: Algorithms for Quantitative Pedology},
    author = {{Beaudette} and {D.} and {Roudier} and {P.} and {Brown} and {A.}},
    note = {R package version 2.0},
    url = {https://CRAN.R-project.org/package=aqp},
    year = {2023},
  }

  Beaudette, D.E., Roudier, P., O'Geen, A.T. Algorithms for
  quantitative pedology: A toolkit for soil scientists, Computers &
  Geosciences, Volume 52, March 2013, Pages 258-268, ISSN 0098-3004,
  http://dx.doi.org/10.1016/j.cageo.2012.10.020.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {Algorithms for quantitative pedology: A toolkit for soil scientists},
    author = {{Beaudette} and {D.E.} and {Roudier} and {P.} and {O'Geen} and {A.T.}},
    journal = {Computers & Geosciences},
    year = {2013},
    volume = {52},
    pages = {258-268},
    url = {http://dx.doi.org/10.1016/j.cageo.2012.10.020},
  }