@article{Andersen1991,
author = {Andersen, P.K. and Hansen, L. and Keiding, N.},
title= {Non-and semi-parametric estimation of transition probabilities from censored observation of a non-homogeneous markov process},
year = {1991},
journal = {Scandinavian Journal of Statistics},
volume = {18},
pages = {153--167},
}