To cite pscl/ideal in publications use

Simon Jackman (2017). pscl: Classes and Methods for R Developed in the Political Science Computational Laboratory. United States Studies Centre, University of Sydney. Sydney, New South Wales, Australia. R package version 1.5.2. URL https://github.com/atahk/pscl/

If count data regression models zeroinfl()/hurdle() are used, please cite:

Achim Zeileis, Christian Kleiber, Simon Jackman (2008). Regression Models for Count Data in R. Journal of Statistical Software 27(8). URL http://www.jstatsoft.org/v27/i08/.

Corresponding BibTeX entries:

  @Manual{,
    title = {{pscl}: Classes and Methods for {R} Developed in the
      Political Science Computational Laboratory},
    author = {Simon Jackman},
    organization = {United States Studies Centre, University of
      Sydney},
    address = {Sydney, New South Wales, Australia},
    year = {2017},
    note = {R package version 1.5.2},
    url = {https://github.com/atahk/pscl/},
  }
  @Article{,
    title = {Regression Models for Count Data in {R}},
    author = {Achim Zeileis and Christian Kleiber and Simon Jackman},
    journal = {Journal of Statistical Software},
    year = {2008},
    volume = {27},
    number = {8},
    url = {http://www.jstatsoft.org/v27/i08/},
  }