To cite the ouch package in publications use:

King AA, Butler MA (2009). ouch: Ornstein-Uhlenbeck models for phylogenetic comparative hypotheses. https://kingaa.github.io/ouch/.

Butler MA, King AA (2004). “Phylogenetic comparative analysis: a modeling approach for adaptive evolution.” American Naturalist, 164, 683–695. doi: 10.1086/426002.

As ouch is continually evolving, you may want to cite its version number. Find it with 'packageVersion("ouch")'.

Corresponding BibTeX entries:

  @Manual{,
    title = {ouch: Ornstein-Uhlenbeck models for phylogenetic
      comparative hypotheses},
    author = {Aaron A. King and Marguerite A. Butler},
    year = {2009},
    url = {https://kingaa.github.io/ouch/},
  }

  @Article{,
    author = {Marguerite A. Butler and Aaron A. King},
    title = {Phylogenetic comparative analysis: a modeling approach for
      adaptive evolution},
    journal = {American Naturalist},
    year = {2004},
    volume = {164},
    pages = {683--695},
    doi = {10.1086/426002},
  }