Examination of the equivalence of self-report survey-based paper-and-pencil and internet data collection methods
Psychological Methods (2013) - Comment
pubmed: 23477606  doi: 10.1037/a0031607  issn: 1939-1463  issn: 1082-989x 

Arne Weigold, Ingrid K. Weigold, Elizabeth J. Russell