Antonio Morassi. Tiepolo. Bergamo, 1943, p. 48, no. 125, pl. 125, identifies this painting as a sketch by Giovanni Battista Tiepolo for the ceiling of the Saleta in the Palacio Real, Madrid, datable about 1764–66, and formerly with the Van Diemen Gallery, Berlin.
F[rancisco]. J[avier]. Sánchez Cantón. J. B. Tiepolo en España. Madrid, 1953, pp. 17–18, believes this is the later of the two sketches for the ceiling of the Saleta [the other sketch being MMA 37.165.3].
Antonio Morassi. G. B. Tiepolo: His Life and Work. London, 1955, p. 150, as one of two sketches for the ceiling of the Saleta.
"Aportaciones recientes a la historia del arte español." Archivo español de arte 34, no. 134 (1961), p. 187, no. 178, pl. 3.
Antonio Morassi. A Complete Catalogue of the Paintings of G. B. Tiepolo. London, 1962, pp. 21, 33, 37, fig. 321.
Goya and His Times. Exh. cat., Royal Academy of Arts. London, 1963, p. 5.
Anna Pallucchini in L'opera completa di Giambattista Tiepolo. Milan, 1968, pp. 130, 132, no. 279 D1, ill., as the later of the two sketches, and the true model for the ceiling of the Saleta.
Claus Virch. "Dreams of Heaven and Earth: Giambattista and Domenico Tiepolo in the Wrightsman Collection." Apollo 90 (September 1969), pp. 175, 178, ill., dates this sketch about 1764, noting that the fresco is an amalgamation of motifs from both of the MMA sketches.
J. Byam Shaw. "The Biron Collection of Eighteenth-Century Drawings in the Metropolitan Museum." Metropolitan Museum Journal 3 (1970), p. 239, comments that "it is difficult to decide which of the two sketches preceded the other".
Oil Sketches by 18th Century Italian Artists from New York Collections. Exh. cat., The Metropolitan Museum of Art. [New York], 1971, p. 9, no. 30, believes this work was executed before the other MMA sketch, as the latter shares more details with the fresco.
Everett Fahy in "Paintings, Drawings." The Wrightsman Collection. 5, [New York], 1973, pp. 248–56, no. 26, ill. (overall in color and details), finds it impossible to judge which of the two sketches is later.
Federico Zeri with the assistance of Elizabeth E. Gardner. Italian Paintings: A Catalogue of the Collection of The Metropolitan Museum of Art, Venetian School. New York, 1973, p. 59, note that of the two sketches this one is closer to the final fresco.
John Pope-Hennessy in The Metropolitan Museum of Art: Notable Acquisitions, 1980–1981. New York, 1981, pp. 44–45, ill. (color), as a "somewhat later study" than the other one in the Museum's collection.
Michael Levey. Giambattista Tiepolo: His Life and Art. New Haven, 1986, pp. 263–64, observes that neither of the existing sketches can claim to be in itself the modello and that both sketches may have been submitted to the King as preliminary ideas; notes that this sketch was executed on a larger canvas and that it quotes the image of the puma that appears in Tiepolo's throne room fresco, but not in the Saleta fresco.
Beverly Louise Brown. Giambattista Tiepolo: Master of the Oil Sketch. Exh. cat., Kimbell Art Museum, Fort Worth. Milan, 1993, pp. 310–12, no. 56, ill. (color), believes that neither of the MMA sketches served as the explicit modello for the finished fresco, which is the synthesis of motifs in both works; suggests that Tiepolo worked on both sketches simultaneously—as he changed the rectangular format to an oval in both works—and that he presented them to Charles III and his advisors as alternatives to choose between.
Massimo Gemin, and Filippo Pedrocco. Giambattista Tiepolo: i dipinti, opera completa. Venice, 1993, pp. 200, 488, no. 518b, ill., believes this work was created after the other Museum sketch.
Rodolfo Pallucchini. La pittura nel Veneto: il Settecento. 1, Milan, 1995, p. 471, as the later of the two MMA sketches; erroneously as still in the Wrightsman collection.
Keith Christiansen et al. in Giambattista Tiepolo, 1696–1770. Exh. cat., The Metropolitan Museum of Art. New York, 1996, pp. 286, 328–33, no. 54b. ill. (color) [Italian ed., Milan, 1996], comments on the many differences in the secondary figures included in this work and the other MMA sketch, noting that the final ceiling incorporates elements of both, at the same time introducing completely new features; observes that the iconographical program of the Saleta was described in detail by Francisco José Fabre in a guide for King Ferdinand VII in 1829.
William L. Barcham. "'E chi non potrebbe cantare facilmente Febo?'." Giambattista Tiepolo nel terzo centenario della nascita. Padua, 1998, vol. 1, pp. 255–56, vol. 2, p. 93, fig. 2, discusses the relative importance Apollo assumes in the two oil sketches and his culminating role in the fresco.
Chantal Eschenfelder. Giovanni Battista Tiepolo, 1696–1770. Cologne, 1998, p. 133.
Everett Fahy in The Wrightsman Pictures. New York, 2005, pp. 96–99, no. 28, ill. (color).
Xavier F. Salomon in Giambattista Tiepolo: "il miglior pittore di Venezia". Exh. cat., Villa Manin di Passariano. Codroipo, 2012, p. 249, under no. 46.