Russian poetry rhythm analysis and probability theory

he following paper was originally obtained from V. V. Ivanov, along with some other materials also pertaining to Russian verse research, which Andrei Nikolaevich Kolmogorov studied actively and with inspiration together with a group of his younger colleagues while Chair of Probability Theory at Moscow University.
The typewritten copy of the manuscript contained nine pages, had no date, and, as far as I know, was never submittedfor publication. One can only make guesses as to why this manuscript was not published: could it be that Kolmogorov considered it unfinished, or that his last check revealed regrettable inaccuracies that had crept into it and he put off publication?
Now, 35 years later (the paper was probably written in 1962), the editors of Theory of Probability and Its Applications, sharing the finally formed conviction that everything Kolmogorov ever wrote should come out, has decided to publish this manuscript.
A. B. Sossinsky, with whom Andrei Nikolaevich discussed these matters quite frequently during the very last years of his life, took an active part in preparing the manuscript for publication. His commentary, as well as notes explaining some notions of the theory of versification for those readers who are not familiar with the issues discussed in the paper, immediately follow the text.