Dr. Blagovo (1867-1940) had married at the age of forty a provincial belle in the Volgan town of Kineshma, a few miles south from one of my most romanic country estates, famous for its wild ravines, now gravel pits or places of massacre, but then magnificent evocations of sunken gardens. (LATH, 2.8)

A namesake of Vadim's second wife Annette Blagovo (Dr. Blagovo's daughter), Anyuta Blagovo is a character in Chekhov's Moya Zhizn'. Rasskaz provintsiala ("My Life. A Provincial's Story", 1896)

In a letter of April 23, 1890, to his sister in Moscow Chekhov, who was heading for Sakhalin (the site of Russian penal colonies), mentions a romantic ravine near Kineshma:

Kundasova* is travelling with me. Where she is going and with what object I don't know. When I question her about it, she launches off into extremely misty allusions about someone who has appointed a tryst with her in a ravine near Kineshma... We have passed both Kineshma and the ravine, but she still goes on in the steamer...

Kostroma is a nice town. I saw Plyos where the languid Levitan used to live.** I saw Kineshma, where I walked along the boulevard and watched the local beaus... The chemist, on seeing Olga Petrovna, was overcome with delight and confusion; she was the same. They were evidently old acquaintances, and judging from the conversation between them they had walked more than once about the ravines near Kineshma.

...Very beautiful are the steam-tugs, dragging after them four or five barges each; they look like some fine young intellectual trying to run away while a plebeian wife, mother-in-law, sister-in-law, and wife's grandmother hold on to his coat-tails... (Chekhov wrote this letter onboard the steamer Alexander Nevsky that brought him from Yaroslavl to Perm.)

"Next after it [Singapore] comes Ceylon—an earthly Paradise. There in that Paradise I went more than a hundred versts on the railway and gazed at palm forests and bronze women to my heart's content...." (from Chekhov's letter of December 9, 1890, to Suvorin)

"I have been in Hell, which is Sakhalin, and in Paradise, which is the island of Ceylon!" (from Chekhov's letter of December 10, 1890, to Leontiev-Shcheglov)

"Ceylon and Jamaica, the sibling islands," are mentioned in LATH's last sentence. Speaking of girls and islands in LATH, note the bermudki, as Ninel Langley indecently calls two ravishing wiggly-bottomed Bermudian coeds who help Annette Blagovo in the kitchen and minister to Vadim's humble needs (2.2).

"Gravel pits" remind one of ugol'naya yama (the coal pit) in VN's poem Otvyazhis', ya tebya umolyayu!... ("To Russia," 1939):

Но зато, о Россия, сквозь слёзы,
сквозь траву двух несмежных могил,
сквозь дрожащие пятна берёзы,
сквозь все то, чем я смолоду жил,

дорогими слепыми глазами
не смотри на меня, пожалей,
не ищи в этой угольной яме,

Slyozy (tears) in this poem and zvyozdy (stars) in Rasstrel bring to mind Vadim's lines in LATH (2.3):

Yes, I definitely felt my family name began with an N and bore an odious resemblance to the surname or pseudonym of a presumably notorious (Notorov? No) Bulgarian, or Babylonian, or, maybe, Betelgeusian writer with whom scatterbrained émigrés from some other galaxy constantly confused me; but whether it was something on the lines of Nebesnyy or Nabedrin or Nablidze (Nablidze? Funny) I simply could not tell. (7.3)

Betelgeuse is a first-magnitude star in the constellation Orion. Vadim suspects that his real father is his benefactor, Nikifor Starov. Is Annette Blagovo Nikifor Starov's daughter? (Btw., Chekhov was forty one when he married Olga Knipper, a leading actress of the Moscow Art Theatre. They had no children.) The Troitski Cathedral of the Alexander Nevsky monastery in St. Petersburg was built by Ivan Starov.