To cite ade4 in publications use:

  Dray S, Dufour A (2007). “The ade4 Package: Implementing the Duality
  Diagram for Ecologists.” _Journal of Statistical Software_, *22*(4),
  1-20. doi:10.18637/jss.v022.i04
  <https://doi.org/10.18637/jss.v022.i04>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {The {ade4} Package: Implementing the Duality Diagram for Ecologists},
    author = {St\'ephane Dray and Anne--B\'eatrice Dufour},
    journal = {Journal of Statistical Software},
    year = {2007},
    volume = {22},
    number = {4},
    pages = {1--20},
    doi = {10.18637/jss.v022.i04},
  }

Bougeard S, Dray S (2018). “Supervised Multiblock Analysis in R with
the ade4 Package.” _Journal of Statistical Software_, *86*(1), 1-17.
doi:10.18637/jss.v086.i01 <https://doi.org/10.18637/jss.v086.i01>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {Supervised Multiblock Analysis in {R} with the {ade4} Package},
    author = {St\'ephanie Bougeard and St\'ephane Dray},
    journal = {Journal of Statistical Software},
    year = {2018},
    volume = {86},
    number = {1},
    pages = {1--17},
    doi = {10.18637/jss.v086.i01},
  }

Chessel D, Dufour A, Thioulouse J (2004). “The ade4 Package - I:
One-Table Methods.” _R News_, *4*(1), 5-10.
<https://cran.r-project.org/doc/Rnews/>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {The {ade4} Package -- {I}: One-Table Methods},
    author = {Daniel Chessel and Anne-B\'eatrice Dufour and Jean Thioulouse},
    journal = {R News},
    year = {2004},
    volume = {4},
    number = {1},
    pages = {5--10},
    url = {https://cran.r-project.org/doc/Rnews/},
  }

Dray S, Dufour A, Chessel D (2007). “The ade4 Package - II: Two-Table
and K-Table Methods.” _R News_, *7*(2), 47-52.
<https://cran.r-project.org/doc/Rnews/>.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {The {ade4} Package -- {II}: Two-Table and {K}-Table Methods},
    author = {St\'ephane Dray and Anne-B\'eatrice Dufour and Daniel Chessel},
    journal = {R News},
    year = {2007},
    volume = {7},
    number = {2},
    pages = {47--52},
    url = {https://cran.r-project.org/doc/Rnews/},
  }

Thioulouse J, Dray S, Dufour A, Siberchicot A, Jombart T, Pavoine S
(2018). _Multivariate Analysis of Ecological Data with ade4_. Springer.
doi:10.1007/978-1-4939-8850-1
<https://doi.org/10.1007/978-1-4939-8850-1>.

A BibTeX entry for LaTeX users is

  @Book{,
    title = {Multivariate Analysis of Ecological Data with {ade4}},
    author = {Jean Thioulouse and St\'ephane Dray and Anne--B\'eatrice Dufour and Aur\'elie Siberchicot and Thibaut Jombart and Sandrine Pavoine},
    year = {2018},
    publisher = {Springer},
    doi = {10.1007/978-1-4939-8850-1},
  }