Bryson Burroughs. "The Island of the Dead by Arnold Böcklin." Metropolitan Museum of Art Bulletin 21 (June 1926), p. 148, refers to it as "presumably one of a number of sketches which are known to have been purchased from [Böcklin] in 1852, possibly by an American traveling in Italy".
Ludwig Thormaehlen. "Böcklins Studien aus den Jahren 1850 und 1851." Repertorium für Kunstwissenschaft 47 (1926), pp. 212–13, fig. 13, calls it "Italienische Landschaft" and dates it 1851; notes that it is among six Böcklin works purchased by Hans Wendland [aside from the thirty one landscapes that he exhibited in "Landschaften von Arnold Böcklin gemalt um 1852," Nationalgalerie, Berlin, August–September 1925]; states that it was obviously painted in the Alban Hills and relates it to "Wald bei Genzano," another painting in the Wendland group.
L[udwig]. Thormaehlen. Letter to Bryson Burroughs. September 25, 1926, states that this painting is certainly among the group [Hans Wendland purchased] in Chicago; surmises that it was painted in the summer of 1850 and that the town on the hill is Olevano; notes that H. A. Schmid does not attribute the Wendland paintings to Böcklin [see Schmid, "Böcklins Frühzeit und die Italienischen Landschaften aus Amerika," Repertorium für Kunstwissenschaft, 47, 1926, pp. 183–91].
Walter Geese. Die Heroische Landschaft von Koch bis Böcklin. Strasbourg, 1930, pp. 137–38, dates it 1852.
Rolf Andree. Arnold Böcklin, 1827–1901. Exh. cat., Hayward Gallery. London, 1971, p. 10, states that he is unable "to relate the so called Wendland paintings of the years 1850/1, in so far as he is familiar with them in the original, to the authenticated paintings of the same period".
Rolf Andree. Letter to John Walsh. September 24, 1974, states that this picture was among those purchased in Chicago by Hans Wendland in the 1920s; doubts that Böcklin sold pictures to an American collector in the 1850s [see Ref. Burroughs 1926] and questions his authorship of this painting; suggests that this was a work on paper pasted to canvas and notes that the brushstrokes are not continuous over joins in a few places.
Rolf Andree. Arnold Böcklin: Die Gemälde. 2nd, supplemented and revised ed. Basel, 1998, p. 20, refutes Thormaehlen's [Ref. 1926, "Repertorium für Kunstwissenschaft"] argument that the Wendland paintings are among Böcklin's first Italian landscapes.
Hans Holenweg. "Die 1924/26 in Amerika aufgetauchten und Arnold Böcklin zugeschriebenen Landschaften—Zur Frage der Autorschaft." Zeitschrift für Schweizerische Archäologie und Kunstgeschichte 63, no. 3 (2006), p. 245, states that Wendland discovered the group of landscapes attributed to Böcklin in Chicago during the winter of 1924–25; argues that these works are by the Swiss painter, Johann Jakob Frey.