To cite package ‘MixedPsy’ in publications use:

  Moscatelli A, Balestrucci P (2017). _Psychophysics with R: The R
  package MixedPsy_. R package version 1.1.0.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {Psychophysics with R: The R package MixedPsy},
    author = {Alessandro Moscatelli and Priscilla Balestrucci},
    year = {2017},
    note = {R package version 1.1.0},
  }

  Moscatelli A, Mezzetti M, Lacquaniti F (2012). “Modeling
  psychophysical data at the population-level: The generalized linear
  mixed model.” _Journal of Vision_, *12*, 1-17.

A BibTeX entry for LaTeX users is

  @Article{,
    title = {Modeling psychophysical data at the population-level: The generalized linear mixed model},
    author = {Alessandro Moscatelli and Maura Mezzetti and Francesco Lacquaniti},
    year = {2012},
    journal = {Journal of Vision},
    volume = {12},
    issue = {11},
    pages = {1--17},
  }