Anders Frederiksen, Bo E. Honore, Luojia Hu, Discrete time duration models with group-level heterogeneity, Journal of Econometrics, Volume 141, Issue 2, December 2007, Pages 1014-1043, ISSN 0304-4076, DOI: 10.1016/j.jeconom.2006.12.003.
(http://www.sciencedirect.com/science/article/B6VC0-4N0PG1K-1/2/e6c9dc4223f2c08a839afeec5d95a6e3)
Keywords: Panel data; Discrete choice; Duration models