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Unobserved heterogeneity in hazard rate models : a test and an ill. from a study of career mobility
Blossfeld, Hans-Peter, (1987)
Bayesian estimation of cost functions with stochastic or exact constraints on parameters
Ilmakunnas, Pekka, (1983)
Der Chi-Quadrat-Test in der Marktforschung
Heyn, Wolfgang, (1962)