Nabokov Book is a term that refers to the works of Russian-American novelist Vladimir Nabokov. The four solutions to the crossword are Lolita, ADA, Dar, and Pnin. Lolita is a novel by Nabokov published in 1955, which tells the story of a middle-aged professor's obsession with a 12-year-old girl. ADA is a novel by Nabokov published in 1969, which follows the lives of two wealthy cousins living in a fictionalized version of 19th century Russia. Dar is a short story by Nabokov published in 1932, which follows the life of a young man who is struggling to find his place in society. Pnin is a novel by Nabokov published in 1957, which follows the life of a Russian professor living in America.