Please read Alexey Sklyarenko's annotations on Pale Fire, Ada and other Nabokov works here.
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), the King saw Disa for the first time at a masked ball in his uncle’s palace:
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) quotes the beginning of a sonnet that Conmal (the king’s uncle, Zemblan translator of Shakespeare) composed directly in English:
Describing the family dinner in "Ardis the Second," Van Veen (the narrator and main character in VN's novel Ada, 1969) mentions Demon's and Marina's petits soupers:
Describing the family dinner in "Ardis the Second," Van Veen (the narrator and main character in VN's novel Ada, 1969) mentions the third sight (individual, magically detailed imagination) that Marina (Van's, Ada's and Lucette's mother) lacks:
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) quotes the beginning of a sonnet that Conmal (the king’s uncle, Zemblan translator of Shakespeare) composed directly in English:
On the day of his death Hugh Person (the main character in VN's novel Transparent Things, 1972) moves to another room of the Ascot Hotel, because the owner of the little spitz dog had returned earlier from his trip and reclaimed his pet with great cries:
In a poem that Humbert Humbert (the narrator and main character in VN's novel Lolita, 1955) makes Clare Quilty (the playwright who abducted Lolita from the Elphinstone hospital) read aloud before murdering him Humbert calls himself a sinner and compares himself to Adam (the first man):
When Humbert Humbert (the narrator and main character in VN's novel Lolita, 1955) visits Lolita (now married to Dick Schiller) in Coalmont, she tells him that Clare Quilty (the playwright with whom Lolita escaped from the Elphinstone hospital) took her to the Duk Duk Ranch:
“Sit down,” she said, audibly striking her flanks with her palms. I relapsed into the black rocker.
“So you betrayed me? Where did you go? Where is he now?”
Before the family dinner in "Ardis the Second" Demon Veen (in VN's novel Ada, 1969, Van's and Ada's father) quotes a poem by François Coppée and mentions Irène de Grandfief, la pauvre et noble enfant, who sold her éléphant:
Here Ada herself came running into the room. Yes-yes-yes-yes, here I come. Beaming!
In the lift of a tall Manhattan building that brings him to Van's penthouse apartment Demon Veen (in VN's novel Ada, 1969, Van's and Ada's father) places a piece of nobler metal among the silver domes on Valerio's rolling table with breakfast for two: