Barrie Karp sent the link to an extremely interesting article about VN's translation of Laughter in the Dark by John Colapinto, Dec. 4, 2014. [http://www.newyorker.com/books/page-turner/nabokov-retranslated-laughter-dark]. The information provided an enjoyable read, too.
From the Wikipedia, while researching a theme related to Chorb/Parsifal, I found news about another duplicated translation: "After its publication in the Russian emigre press the story was translated into English by Gleb Struve as The Return of Tchorb and published in the Paris magazine This Quarter in 1932. More than four decades later Nabokov retranslated the story, as he found Struve's translation "not accurate enough and far removed from my present use of English", and incorporated the story in the collection Details of a Sunset and Other Stories in 1976. The two English translations are very different and represent an interesting study on Nabokov's theory of translation”*.
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*-The wiki note gives, as a reference the work of Robert Meyer. “Nabokov: A Case Study in the Art of Translation.”