To cite adabag in publications use:

  Alfaro, E., Gamez, M. Garcia, N.(2013). adabag: An R Package for
  Classification with Boosting and Bagging. Journal of Statistical
  Software, 54(2), 1-35. DOI https://doi.org/10.18637/jss.v054.i02

A BibTeX entry for LaTeX users is

  @Article{,
    title = {{adabag}: An {R} Package for Classification with Boosting and Bagging},
    author = {Esteban Alfaro and Matías Gámez and Noelia García},
    journal = {Journal of Statistical Software},
    year = {2013},
    volume = {54},
    number = {2},
    pages = {1--35},
    doi = {10.18637/jss.v054.i02},
  }