\Bibitem{GolChi86} \by O.~N.~Gol'tyaeva, V.~P.~{\v C}istyakov \paper On the estimation of the criticality parameter of a~branching process with immigration \jour Teor. Veroyatnost. i Primenen. \yr 1986 \vol 31 \issue 4 \pages 784--788 \mathnet{http://mi.mathnet.ru/tvp1687} \mathscinet{http://mathscinet.ams.org/mathscinet-getitem?mr=881588} \zmath{https://zbmath.org/?q=an:0657.62101|0616.62112} \transl \jour Theory Probab. Appl. \yr 1987 \vol 31 \issue 4 \pages 693--697 \crossref{https://doi.org/10.1137/1131093} \isi{https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=Publons&SrcAuth=Publons_CEL&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=A1987K866700013}