To cite 'basicspace' in publications use:

  Keith Poole, Jeffrey Lewis, Howard Rosenthal, James Lo, Royce Carroll
  (2016). Recovering a Basic Space from Issue Scales in R. Journal of
  Statistical Software, 69(7), 1-21. doi:10.18637/jss.v069.i07

A BibTeX entry for LaTeX users is

  @Article{,
    entry = {Article},
    title = {Recovering a Basic Space from Issue Scales in {R}},
    author = {Royce Carroll and Christopher Hare and Jeffrey B. Lewis and James Lo and Keith T. Poole and Howard Rosenthal},
    journal = {Journal of Statistical Software},
    year = {2016},
    volume = {69},
    number = {7},
    pages = {1--21},
    doi = {10.18637/jss.v069.i07},
  }