I found this tidbit in the archives from 2002
EDNOTE. Yes, It is the same Martin Gardner, long-time columnist for
_Scientific American_ and author of many fascinating books, as well as
annotated eiditons of such works as _Alice in Wonderland_ He and Nabokov had
a protracted exchange in some of their books over a period of years. I
discussed the exchange in a article some years ago: Johnson, D[onald]
Barton: "The Ambidextrous Universe of Nabokov's Look at the Harlequins!".
In: Critical Essays on Vladimir Nabokov (ed. Phyllis A. Roth). Boston, MA:
G.K. Hall, 1984, pp. 202-214. Another version may be found in my book Worlds
in Regression.