\Bibitem{Shp68} \by D.~I.~Shparo \paper Some ways of completing the phase space of a~Markov chain \jour Teor. Veroyatnost. i Primenen. \yr 1968 \vol 13 \issue 2 \pages 341--344 \mathnet{http://mi.mathnet.ru/tvp852} \mathscinet{http://mathscinet.ams.org/mathscinet-getitem?mr=232452} \zmath{https://zbmath.org/?q=an:0181.44803|0167.17003} \transl \jour Theory Probab. Appl. \yr 1968 \vol 13 \issue 2 \pages 327--329 \crossref{https://doi.org/10.1137/1113038}