Mariano Guardabassi. Indice-guida dei monumenti pagani e cristiani riguardanti l'istoria e l'arte esistenti nella provincia dell'Umbria. [reprint, 1968]. Bologna, 1872, p. 157, lists four works by an artist of the fourteenth-century Sienese school in the Palazzo Mazzocchi, Orvieto: Saint Anthony Abbot with Saint John the Evangelist above, Saint Nicholas of Bari, Saint Stephen with the Virgin of the Annunciation above, and an unidentified male saint with the angel of the Annunciation above; possibly the MMA panels.
Bernhard Berenson. The Central Italian Painters of the Renaissance. 2nd ed., rev. and enl. New York, 1909, p. 257, as in the collection of Theodore M. Davis, Newport; lists the four panels as by Taddeo di Bartolo.
Joseph Breck. "Dipinti italiani nella raccolta del Signor Teodoro Davis." Rassegna d'arte 11 (July 1911), p. 114, attributes the four panels to Taddeo di Bartolo or a close follower; identifies this figure as Saint Paul.
F. Mason Perkins. "Some Sienese Paintings in American Collections: Part Three." Art in America 9 (December 1920), p. 11, fig. 3, as formerly in the collection of the late Theodore Davis and now in the Metropolitan Museum; attributes the four panels to Martino di Bartolommeo; tentatively identifies this figure as either Saint Galganus or Saint Julian.
Raimond van Marle. The Development of the Italian Schools of Painting. Vol. 2, The Sienese School of the 14th Century. The Hague, 1924, pp. 588, 590, attributes the four panels to Martino and mentions their similarity to three figures of saints by the same artist dated 1408 (Palazzo Pubblico, Siena); states that the four MMA panels were formerly in Orvieto, but, erroneously, that they have been sold to a collector in Boston; identifies this figure as Saint Ansanus.
F. Mason Perkins. "Su alcune pitture di Martino di Bartolommeo." Rassegna d'arte senese 17, nos. 1–2 (1924), p. 11 n. 2.
[Curt H.] Weigelt in Allgemeines Lexikon der bildenden Künstler. Vol. 24, Leipzig, 1930, p. 180, as in the Metropolitan Museum; attributes the four panels to Martino and dates them close to the three standing saints of 1408 in the Palazzo Pubblico, Siena; identifies this figure as Saint Galganus.
Bernhard Berenson. Italian Pictures of the Renaissance. Oxford, 1932, p. 333, attributes them to Martino; identifies this figure as Saint Galganus.
George Rowley. Letter to Margaretta Salinger. September 19, 1932, rejects the identification of the figure as Saint Galganus, suggesting instead Saint Ansanus or possibly Saint Victor.
Bernhard Berenson. Pitture italiane del rinascimento. Milan, 1936, p. 296.
Harry B. Wehle. The Metropolitan Museum of Art: A Catalogue of Italian, Spanish, and Byzantine Paintings. New York, 1940, pp. 85–86, attributes them to Martino; identifies this figure as Saint Julian of Cilicia.
F[ederico]. Zeri. "La mostra della pittura viterbese." Bollettino d'arte 40 (January–March 1955), pp. 86–87, fig. 1, attributes them to Martino and dates them to the first decade of the 15th century; compares them with two panels in the church of Sant'Agostino in Bagnoregio, near Orvieto.
Sibilla Symeonides. Taddeo di Bartolo. Siena, 1965, p. 256, lists three of the panels among school and rejected works, omitting the Saint Stephen (30.95.263).
Bernard Berenson. Italian Pictures of the Renaissance: Central Italian and North Italian Schools. London, 1968, vol. 1, p. 246, calls them four panels of a polyptych from Orvieto; identifies this figure as Saint Galganus and the pinnacle figure merely as a bishop.
Burton B. Fredericksen and Federico Zeri. Census of Pre-Nineteenth-Century Italian Paintings in North American Public Collections. Cambridge, Mass., 1972, pp. 122, 421, 435, 607.
Federico Zeri with the assistance of Elizabeth E. Gardner. Italian Paintings: A Catalogue of the Collection of The Metropolitan Museum of Art, Sienese and Central Italian Schools. New York, 1980, pp. 33–35, pl. 31, call them lateral panels from an altarpiece whose central panel was probably a Madonna and Child enthroned; place the Saint Anthony Abbot with the pinnacle of Saint John the Baptist at the inside left of the altarpiece because the Baptist's gesture and scroll refer to the missing Madonna and Child, noting that the pinnacles with the Annunciation also refer to these missing figures; date the panels about 1410, based on comparison with the three saints by Martino dated 1408 in the Palazzo Pubblico, Siena; believe it "quite possible" that they were executed for a church in or near Orvieto, comparing them with the two panels in the church of Sant'Agostino, Bagnoregio, not far from Orvieto; tentatively identify this figure as Saint Julian the Hospitaller.
Mojmír S. Frinta. "Part I: Catalogue Raisonné of All Punch Shapes." Punched Decoration on Late Medieval Panel and Miniature Painting. Prague, 1998, p. 520, classifies a punch mark appearing in this painting.
Carl Brandon Strehlke and Machtelt Brüggen Israëls. The Bernard and Mary Berenson Collection of European Paintings at I Tatti. Florence, 2015, p. 752, no. 69, ill.
Machtelt Brüggen Israëls in Carl Brandon Strehlke and Machtelt Brüggen Israëls. The Bernard and Mary Berenson Collection of European Paintings at I Tatti. Florence, 2015, pp. 60, 69 n. 137, quotes from three letters from Bernard Berenson to his future wife, Mary Costelloe, in which he mentions these four panels; notes that while in Bernard and Mary's collection, the works hung in Mary's rented house, Il Frullino, in Florence.