In April 1974, aged 75, Nabokov completed what was to be his last published novel, Look at the Harlequins! That same month he signed a four-year contract with McGraw-Hill for a further six books – his next novel, The Original of Laura, which he was ready to start, as well as newly-translated volumes of short stories, his Russian plays, and a selection of nineteenth- and twentieth-century Russian verse. It was as if the completion of Look at the Harlequins! gave Nabokov a new lease of life: during work on the novel he was preoccupied by a fear that he would not be able to finish it. For the first time in his career he made a point of keeping the index cards on which he composed in their correct order by …
Wyllie, Barbara. "Look at the Harlequins!". The Literary Encyclopedia. First published 24 April 2007; last revised 30 November -1.
[http://www.litencyc.com/php/sworks.php?rec=true&UID=3920, accessed 28 April 2015.]