“…For diffusions and other continuous-state processes, a good starting point is Steinsaltz and Evans [140] (but see also Cattiaux et al [22] and Pinsky [119]) and for branching processes there is an excellent recent review by Lambert [95,Section 3]. Whilst many issues remain unresolved, the theory has reached maturity, and the use of quasi-stationary distributions is now widespread, encompassing varied and contrasting areas of application, including cellular automata (Atman and Dickman [9]), complex systems (Collet et al [34]), ecology (Day and Possingham [41], Gosselin [63], Gyllenberg and Sylvestrov [68], Kukhtin et al [89], Pollett [122]) epidemics (Nåsell [106,107,108], Artalejo et al [6,7]), immunology (Stirk et al [141]), medical decision making (Chan et al [24]), physical chemistry (Dambrine and Moreau [37,38], Oppenheim et al [112], Pollett [121]), queues (Boucherie [17], Chen et al [25], Kijima and Makimoto [84]), reliability (Kalpakam and Shahul-Hameed [73], Kalpakam [74], Li and Cao [98,99]), survival analysis (Aalen and Gjessing [1,2], Steinsaltz and Evans [139]) and telecommunications (Evans [53], Ziedins [152]).…”