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Population Processes with Immigration
P. 411–434.
Han D., Molchanov S., Whitmeyer J.
The paper contains a complete analysis of the Galton–Watson models with immigration, including the processes in the random environment, stationary or nonstationary ones. We also study the branching random walk on $Z^d$ with immigration and prove the existence of the limits for the first two correlation functions.
In book
Heidelberg: Springer, 2017.