Before revision:  We focus on the Expectation-Maximization (EM) algorithm by \mbox{%DIFAUXCMD BladtSorensen2005 for a CTMC with an absorbing state for such estimation.
After revision:  We focus on the Expectation-Maximization (EM) algorithm by Bladt and Sorensen (2005) for a CTMC with an absorbing state for such estimation.