Another book that Evgeny Belodubrovsky would like to point out:

Miry i antimiry Vladimira Nabokova, 2011

It is D. Barton Johnson’s Miry i antimiry: Vladimira Nabokova, published in 2011 by Symposium in St. Petersburg, ISBN 978-5-89091-445-3. The book is a Russian translation of Johnson’s 1985 book, Worlds in Regression: Some Novels of Vladimir Nabokov, a study in 12 essays of the “games” Nabokov plays in his novels.

Referring to my previous post of information from Belodubrosky: The Guadanini book of letters, Pis’ma, can be bought from the Russian book dealer Ozon. (Here’s a link to the book on Ozon’s website: http://www.ozon.ru/context/detail/id/18088151.) Also, Belodubrovsky says that the Dva puti semi-facsimile is out of stock and that he is working with the publisher to get it to print some more.