Penguin Paperback Variations on Nabokov's Dozen

Sources: Alexis Orloff and Samuel Snoek-Brown. 

Nabokovilia: Nabokov's Creepy Bathtub in Gibson's Spook Country

Susan Elizabeth Sweeney spotted the reference and posted it in the Nabokov-L forum: Gibson's character, Milgrim, Sweeney explains, "is traveling in a Zodiac, an inflatable motorized boat." The quote follows:

He was bouncing along at some insane speed on something that reminded him of a creepy folding rubber bathtub that he'd once seen Vladimir Nabokov posing with in an old photograph. (344)