Imai, Kosuke, and David A. Van Dyk. “MNP: R Package for Fitting the Multinomial Probit Model”.
Journal of Statistical Software
14, no. 3 (May 8, 2005): 1–32. Accessed April 6, 2025. https://www.jstatsoft.org/index.php/jss/article/view/v014i03.