1. Ahlquist, J., Breunig, C.: Country clustering in comparative political economy. MPIfG Discussion Paper 09/5, Max Planck Institute for the Study of Societies (2009)
2. Ahlquist, J., Breunig, C.: Model-based clustering and typologies in the social sciences. Polit. Anal. 20(1), 92–112 (2012)
3. Baker, F.B.: Stability of two hierarchical grouping techniques case 1: sensitivity to data errors. J. Am. Stat. Assoc. 69, 440–445 (1974)
4. Esping-Andersen, G.: The Three Worlds of Welfare Capitalism. Princeton University Press, New Jersey (1990)
5. Fowlkes, E.B., Mallows, C.L.: A method for comparing two hierarchical clusterings. J. Am. Stat. Assoc. 78(383), 553–569 (1983)