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The asymptotic posterior normality of the latent trait for polytomous IRT models
Chang, Hua-Hua, (1996)
A rasch model for partial credit scoring
Masters, Geoff, (1982)
An extension of the rasch model for ratings providing both location and dispersion parameters
Andrich, David, (1982)
A latent class model for rating data
Rost, Jürgen, (1985)