1. Borg, I., Groenen, J.F.P.: Modern Multidimensional Scaling, 2nd edn. Springer, New York (2005)
2. Busing, F.M.T.A.: Avoiding degeneracy in metric unfolding by penalizing the intercept. Br. J. Math. Stat. Psychol. 59, 419–427 (2006)
3. Carroll, J. D.: Individual differences and multidimensional Scaling. In: Shepard, R.N., Romney, A.K., Nerlove, S. (eds.) Multidimensional Scaling: Theory and Applications in the Behavior Sciences, Vol. I: Theory, pp. 105–155. Seminar Press, New York (1972)
4. Carroll, J. D.: Models and methods for multidimensional analysis of preferential choice (or other dominance) data. In: Lantermann, E.D., Feger, H. (eds.) Proceedings of Aachen Symposia on Decision Making and Multidimensional Scaling. Springer Verlag, Berlin (1980)
5. Coombs, C.H.: A Theory of Data. Wiley (1964)