To cite coneproj in publications use:

Xiyue Liao, Mary C. Meyer (2014). coneproj: An R Package for the Primal or Dual Cone Projections with Routines for Constrained Regression. Journal of Statistical Software, 61(12), 1-22. URL http://www.jstatsoft.org/v61/i12/.

Corresponding BibTeX entry:

  @Article{,
    title = {{coneproj}: An {R} Package for the Primal or Dual Cone
      Projections with Routines for Constrained Regression},
    author = {Xiyue Liao and Mary C. Meyer},
    journal = {Journal of Statistical Software},
    year = {2014},
    volume = {61},
    number = {12},
    pages = {1--22},
    url = {http://www.jstatsoft.org/v61/i12/},
  }