To cite package 'difR' in publications use:
Magis D, Beland S, Tuerlinckx F, De Boeck P (2010). “A general framework and an R package for the detection of dichotomous differential item functioning.” Behavior Research Methods, 42, 847–862.
Corresponding BibTeX entry:
@Article{, title = {A general framework and an R package for the detection of dichotomous differential item functioning}, author = {D. Magis and S. Beland and F. Tuerlinckx and P. {De Boeck}}, journal = {Behavior Research Methods}, year = {2010}, volume = {42}, pages = {847--862}, }