Question: When did Salvador Dali paint Swans Reflecting Elephants?
About the article "Swans Reflecting Elephants", section "Abstract".

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Swans Reflecting Elephants (1937) is a painting by the Spanish surrealist Salvador Dalí.
This painting is from Dalí's Paranoiac-critical period.
Painted using oil on canvas, it contains one of Dalí's famous double images.
The double images were a major part of Dalí's "paranoia-critical method," which he put forward in his 1935 essay "The Conquest of the Irrational."
He explained his process as a "spontaneous method of irrational understanding based upon the interpretative critical association of delirious phenomena."
Dalí used this method to bring forth the hallucinatory forms, double images and visual illusions that filled his paintings during the Thirties.
As with earlier "Metamorphosis of Narcissus", "Swans Reflecting Elephants" uses the reflection in a lake to create the double image seen in the painting.
In "Metamorphosis", the reflection of Narcissus is used to mirror the shape of the hand on the right of the picture.
Here, the three swans in front of bleak, leafless trees are reflected in the lake so that the swans' heads become the elephants' heads and the trees become the bodies of the elephants.
In the background of the painting is a Catalonian landscape depicted in fiery fall colors, the brushwork creating swirls in the cliffs that surround the lake, to contrast with the stillness of the water 
The elephant is a recurring theme in the works of Dalí, first appearing in his 1944 work "Dream Caused by the Flight of a Bee Around a Pomegranate a Second Before Awakening", and also in "The Temptation of Saint Anthony" and "Swans Reflecting Elephants.
"The Elephants" differs from the other paintings in that the animals are the primary focus of the work, with a barren graduated background and lack of other content, where most of Dalí's paintings contain much detail and points of interest (for example Swans Reflecting Elephants which is somewhat better known within Dalí's repertoire than "The Elephants".
The stork-legged elephant is one of the best-known icons of Dalí's work and adorn the walls of the Dalí Museum in Spain. 
Dalí produced over 1,500 paintings in his career in addition to producing illustrations for books, lithographs, designs for theatre sets and costumes, a great number of drawings, dozens of sculptures, and various other projects, including an animated short film for Disney.
He also collaborated with director Jack Bond in 1965, creating a movie titled "Dalí in New York".
Below is a chronological sample of important and representative work, as well as some notes on what Dalí did in particular years.
In Carlos Lozano's biography, "Sex, Surrealism, Dalí, and Me", produced with the collaboration of Clifford Thurlow, Lozano makes it clear that Dalí never stopped being a surrealist.
As Dalí said of himself: "the only difference between me and the surrealists is that I am a surrealist."
Dalí returned to Catalonia this year 1951 "Christ of Saint John of the Cross" and "Exploding Raphaelesque Head" 1951 Katharine Cornell, a portrait of the famed actress 1952 "Galatea of the Spheres" 1954 "The Disintegration of the Persistence of Memory" (begun in 1952), "Crucifixion (Corpus Hypercubus)" and "Young Virgin Auto-Sodomized by the Horns of Her Own Chastity" 1955 "The Sacrament of the Last Supper", "Lonesome Echo", record album cover for Jackie Gleason 1956 "Still Life Moving Fast", "Rinoceronte vestido con puntillas" 1957 "Santiago el Grande" oil on canvas on permanent display at Beaverbrook Art Gallery in Fredericton, NB, Canada 1958 "The Meditative Rose" 1959 "The Discovery of America by Christopher Columbus" 1960 "Composición Numérica (de fond préparatoire inachevé)]" 1960 Dalí began work on the Teatro-Museo Gala Salvador Dalí and "Portrait of Juan de Pareja, the Assistant to Velázquez" 1963–1964 "They Will All Come from Saba" a work in water color depicting the Magi at St. Petersburg's Dalí Museum 1965 Dalí donates a gouache, ink and pencil drawing of the Crucifixion to the Rikers Island jail in New York City.
The drawing hung in the inmate dining room from 1965 to 1981 1965 "Dalí in New York" 1967 "Tuna Fishing" 1969 Chupa Chups logo 1969 "Improvisation on a Sunday Afternoon", television collaboration with the British progressive rock group Nirvana 1970 "The Hallucinogenic Toreador", acquired in 1969 by A. Reynolds Morse & Eleanor R. Morse before it was completed 1972 "La Toile Daligram", "Helena Devulina Diakanoff – dit., GALA" 1973 "Le Diners De Gala", an ornately illustrated cook book 1976 "Gala Contemplating the Mediterranean Sea" 1977 "Dalí's Hand Drawing Back the Golden Fleece in the Form of a Cloud to Show Gala Completely Nude, Very Far Away Behind the Sun" (stereoscopical pair of paintings) 1983 Dalí completes his final painting, "The Swallow's Tail" Posthumous 2003 , an animated short film originally a collaboration between Dalí and Walt Disney, is released.
Production on began in 1945 The largest collections of Dalí's work are at the Dalí Theatre and Museum in Figueres, Catalonia, Spain, followed by the Salvador Dalí Museum in St. Petersburg, Florida, which contains the collection of A. Reynolds Morse & Eleanor R. Morse.
It holds over 1,500 works from Dalí.
Other particularly significant collections include the Reina Sofia Museum in Madrid and the Salvador Dalí Gallery in Pacific Palisades, California.
Espace Dalí in Montmartre, Paris, France, as well as the Dalí Universe in London, England, contain a large collection of his drawings and sculptures.
The unlikeliest venue for Dalí's work was the Rikers Island jail in New York City; a sketch of the Crucifixion he donated to the jail hung in the inmate dining room for 16 years before it was moved to the prison lobby for safekeeping.
Ironically, the drawing was stolen from that location in March 2003 and has not been recovered. 
 Athanase Dali (born 1967), Ivorian rugby union player Bikash Lal Dali (born 1980), Nepalese cricketer Gala Dalí (1894–1982), model, Salvador Dalí's wife Gizela Dali (1940–2010), Greek actress Kenza Dali (born 1991), French footballer  Salvador Dalí (1904–1989), Spanish surrealist artist Sudiat Dali (born 1962), Singaporean footballer Tracy Dali (born 1975), American actress and model Wissem Dali (born 1995), Algerian volleyball player Wang Dali (born 1968), Chinese Olympic swimmer Zhang Dali (born 1963), Chinese artist in Beijing