To cite the 'errum' R package and methods paper in publications use:

  Balamuta, J. J., Culpepper, S. A., and Douglas, J. A. (2019). errum:
  Bayesian Estimation of an Exploratory Reduced Reparameterized Unified
  Model. URL https://cran.r-project.org/package=errum.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {{errum: Bayesian Estimation of an Exploratory Reduced Reparameterized Unified Model}},
    author = {James Joseph Balamuta and Steven Andrew Culpepper and Jeffrey A. Douglas},
    year = {2019},
  }

  Culpepper, S. A. and Chen, Y. (2019). Development and Application of
  an Exploratory Reduced Reparameterized Unified Model. Journal of
  Educational and Behavioral Statistics. 44, 3-24. DOI:
  10.3102/1076998618791306.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {{Development and Application of an Exploratory Reduced Reparameterized Unified Model}},
    author = {Steven Andrew Culpepper and Yinghan Chen},
    journal = {Journal of Educational and Behavioral Statistics},
    year = {2019},
    url = {https://doi.org/10.3102/1076998618791306},
    volume = {44},
    number = {1},
    pages = {3-24},
    doi = {10.3102/1076998618791306},
  }