Please read Alexey Sklyarenko's annotations on Pale Fire, Ada and other Nabokov works here.
Describing the family dinner in "Ardis the Second," Van Veen (the narrator and main character in VN’s novel Ada, 1969) says that Demon (Van's and Ada's father) sat next to Marina (Van's, Ada's and Lucette's mother) at the Praslin’s last Christmas:
Describing the family dinner in "Ardis the Second," Van Veen (the narrator and main character in VN’s novel Ada, 1969) mentions the French cuisine that had contributed its chaudfroids and foie gras:
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 Gradus’s puny ghost, shargar:
According to 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), at one time young Gradus (Shade's murderer) studied pharmacology in Zurich, and at another, traveled to misty vineyards as an itinerant wine taster:
One of the three main characters in VN’s novel Pale Fire (1962), Jakob Gradus (Shade’s murderer) is a son of Martin Gradus, a Protestant minister in Riga:
According to 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), after the death of her husband the mother of Jakob Gradus (Shade's murderer) moved to Strasbourg:
At the picnic on her twelfth birthday Ada (the title character of a novel, 1969, by VN) tells Mlle Larivière (the governess of Van's and Ada's half-sister Lucette) that things like menstruations hardly ever happen to normal girls today and will certainly not occur in her case:
In VN’s novel Transparent Things (1972) Mr. R.’s publisher receives Mr. R.’s last letter on the day of Mr. R.’s death:
Dear Phil,
This, no doubt, is my last letter to you. I am leaving you. I am leaving you for another even greater Publisher. In that House I shall be proofread by cherubim - or misprinted by devils, depending on the department my poor soul is assigned to. So adieu, dear friend, and may your heir auction this off most profitably.
In VN’s novel Transparent Things (1972) the spectral narrators discuss the history of a pencil:
The action in VN's novel Ada (1969) takes place on Demonia, Earth's twin planet also known as Antiterra. Describing the difference between Terra and Antiterra, Van Veen mentions the L disaster whose details are too well-known historically, and too obscene spiritually, to be treated at length in a book addressed to young laymen and lemans — and not to grave men or gravemen: