1. Maximum likelihood from incomplete data via the EM algorithm;Dempster;Journal of the Royal Statistical Society, Series B,1977
2. Multivariate Analysis: Methods and Applications;Dillon,1984
3. How many clusters are best? — an experiment;Dubes;Pattern Recognition,1987
4. Pattern Recognition and Scene Analysis;Duda,1973
5. Finite Mixture Distributions. Monographs on Applied Probability and Statistics;Everitt,1981