Please read Alexey Sklyarenko's annotations on Pale Fire, Ada and other Nabokov works here.
In his Commentary to Shade’s poem Kinbote (in VN’s novel Pale Fire, 1962, Shade’s mad commentator who imagines that he is Charles the Beloved, the last self-exiled king of Zembla) mentions Repburg, a landscaper of genius:
Line 49: shagbark
At the picnic on Ada’s sixteenth birthday Marina (in VN’s novel Ada, 1969, Van’s, Ada’s and Lucette’s mother) calls Hollywood “Houssaie, Gollivud-tozh:”
Imagining his duel with Andrey Vinelander (Ada’s husband), Van Veen (the narrator and main character in VN’s novel Ada, 1969) says that the bullet of his adversary caused a slight fourmillement (excited ants) in his foot:
On the eve of his last and longest (seventeen-year-long) separation with Ada (who refuses to leave her ill husband, Andrey Vinelander) Van Veen (the narrator and main character in VN’s novel Ada, 1969) returns from a trip to Sorcière where he bought a villa for himself and Ada (officially, Van’s cousin) and had supper with the former owner, a banker’s widow, amiable Mme Scarlet and her blond, pimply but pretty, daughter Eveline:
Describing the decline of Villa Venus (Eric Veen’s floramors), Van Veen (the narrator and main character in VN’s novel Ada, 1969) mentions the Rajah of Cachou (an impostor) who was infected with a venereal disease by a (genuine) great-grandniece of Empress Josephine:
According to Van Veen (the narrator and main character in VN’s novel Ada, 1969), a set of Flavita (Russian Scrabble) was given to Marina’s children (Van, Ada and Lucette) by Baron Klim Avidov:
Telling Van that she has to finish a translation for Mlle Larivière (Lucette’s governess), Ada says that she will be down in exactly sixty-three minutes:
The main character in VN’s novel Bend Sinister (1947), Adam Krug is a celebrated philosopher. In Chapter One (XXIII: 14) of Eugene Onegin Pushkin calls Onegin "a philosopher at eighteen years of age:"
Изображу ль в картине верной
Уединенный кабинет,
Где мод воспитанник примерный
Одет, раздет и вновь одет?
Because her fingernails are badly bitten, Ada introduces the view to Van (who just came to Ardis and had tea with Marina and Ada) pollice verso (Lat., thumbs down):
On the morning following the Night of the Burning Barn (when they make love for the first time) Van and Ada agree to go for a walk before lunch and find a secluded place and Ada tells Van to wait for her in the Baguenaudier Bower: