To cite basicspace in publications use:

Poole K, Lewis J, Rosenthal H, Lo J, Carroll R (2016). “Recovering a Basic Space from Issue Scales in R.” Journal of Statistical Software, 69(7), 1–21. doi: 10.18637/jss.v069.i07.

Corresponding BibTeX entry:

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