To cite the lsr package in publications use:

  Navarro, D. J. (2015) Learning statistics with R: A tutorial for
  psychology students and other beginners. (Version 0.6) University of
  New South Wales. Sydney, Australia

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {Learning statistics with R: A tutorial for psychology students and other beginners. (Version 0.6)},
    author = {Danielle Navarro},
    organization = {University of New South Wales},
    address = {Sydney, Australia},
    year = {2015},
    note = {R package version 0.5.1},
    url = {https://learningstatisticswithr.com},
  }