Sojourn time in a given state of two independent semi-Markov processes
English version (Springer): Ukrainian Mathematical Journal 20 (1968), no. 6, pp 723-725.
Citation Example: Kovaleva L. M. Sojourn time in a given state of two independent semi-Markov processes // Ukr. Mat. Zh. - 1968. - 20, № 6. - pp. 837–841.
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