To cite package ‘lambda’ in publications use:

Hester J (2015). lambda: Simple anonymous functions. R package version 0.0.0.9000, https://github.com/jimhester/lambda.

Corresponding BibTeX entry:

  @Manual{,
    title = {lambda: Simple anonymous functions},
    author = {Jim Hester},
    year = {2015},
    note = {R package version 0.0.0.9000},
    url = {https://github.com/jimhester/lambda},
  }