The central argument of the provenance chain of the picture is the “Bonger number” on the back of the canvas. This number refers to a list that Andries Bonger drew up in 1890. In this it was listed under number 180 as ”soleil coucant à Arles”. “The subject and size of the picture match that description, but the clinching piece of evidence is simply that the number 180 is written on the back of the canvas.” “The handwriting,” the authors continues, “resembles that on Wheatfield with setting sun, now in the Kunstmuseum, Winterthur, which is also marked with a Bonger number.”