To cite glmertree in publications use:

Fokkema M, Smits N, Zeileis A, Hothorn T, Kelderman H (2018). “Detecting Treatment-Subgroup Interactions in Clustered Data with Generalized Linear Mixed-Effects Model Trees.” Behavior Research Methods, 50, 2016-2034. doi:10.3758/s13428-017-0971-x.

If you use glmertree for growth curve modeling, please also cite:

Fokkema M, Zeileis A (2024). “Subgroup Detection in Linear Growth Curve Models with Generalized Linear Mixed Model (GLMM) Trees.” Behavior Research Methods, 56, 6759–6780. doi:10.3758/s13428-024-02389-1.

Corresponding BibTeX entries:

  @Article{,
    title = {Detecting Treatment-Subgroup Interactions in Clustered
      Data with Generalized Linear Mixed-Effects Model Trees},
    author = {Marjolein Fokkema and Niels Smits and Achim Zeileis and
      Torsten Hothorn and Henk Kelderman},
    journal = {Behavior Research Methods},
    year = {2018},
    volume = {50},
    issue = {5},
    pages = {2016-2034},
    doi = {10.3758/s13428-017-0971-x},
  }

  @Article{,
    title = {Subgroup Detection in Linear Growth Curve Models with
      Generalized Linear Mixed Model ({GLMM}) Trees},
    author = {Marjolein Fokkema and Achim Zeileis},
    journal = {Behavior Research Methods},
    year = {2024},
    volume = {56},
    issue = {7},
    pages = {6759--6780},
    doi = {10.3758/s13428-024-02389-1},
  }