In his catasto of 1427, Donatello lists 15 florins that he owes to Giovanni di Jacopo degli Strozza for the "repeated bronze casting of the figure of St. Rossore and other things". The bust is not mentioned in Michelozzo's contemporaneous 'tax return', which excludes his involvement, Janson 1957, p. 56f. Also Anita Moskowitz, Donatello's Reliquary Bust of Saint Rossore. In: The Art Bulletin, Vol. 63, No. 1 (March 1981), pp. 41–48. Online as pdf on JSTOR
Anita Moskowitz, Donatello's Reliquary Bust of Saint Rossore. In: The Art Bulletin, Vol. 63, No. 1 (March 1981), p. 41–48. Online als pdf on JSTOR.
nga.gov
In the online catalogue of the National Gallery this sculpture is consciously described as "Florentine, 15th Century". In the catalogue of the 2022/23 touring exhibition Aldo Galli identifies it as by Donatello and the earliest example of this sculptural type of Madonna and Child, which subsequently replaced corresponding panel paintings. In Caglioti, p. 120.
Entry in the Wallace Collection's online catalogue. The collection contains another, very similar piece, but without the conch (Inv. S300); there is also a smaller plaquette (Inv. S301), which is believed to have originated in Padua and is dated around 1450.