References
- Kempf-Leonard , K. 2005 . Encyclopedia of Social Measurement , Edited by: Kempf-Leonard , K. Amsterdam : Elsevier .
- Runn-Rankin , P. , Knezek , G. A. , Wallace , S. and Zhang , S. 2004 . Scaling Methods , Mahwah : Lawrence Eerlbaum Associates .
- van der Ven , A. H.G.S. 1980 . Introduction to Scaling , Chichester : Wiley .