The above article was published with an imprecise reference for Ferrari and Martinez [1] (numbered originally as [8] in the article). The correct reference is the subsequent work from 1998 of Ferrari and Martínez [2], entitled Hamiltonians on random walk trajectories and published on Stochastic Processes and their Applications.
The authors would also like to point out that the previous work of Ferrari and Martínez (1993) introduces a continuous fraction approach on chain sequences to study the existence of quasi stationary distributions, which is also relevant, but the notion of Hamiltonians on random walk trajectories was introduced in their subsequent work from 1998.
The updated references are shown below.