V. Manners/G. C. Williamson, Angelica Kauffmann, R. A., Her Life and Her Works, London 1924, p. 190;
D. Moulton Mayer, Angelica Kauffmann, R. A. 1741-1807. A Biography, Gerrards Cross 1972, fig. 21 (Immortalia);
S. Roettgen, in: Österreichische Künstler und Rom: vom Barock zur Secession, exhibition catalogue, ed. by J. Garms, Rome/Vienna 1972, pp. 139-140, cat. no. 151, pl. 65 (Nymphe der Unsterblichkeit) and cat. no. 152, pl. 66 (erroneously as Flora instead of Silvia and Daphne) (as Kauffmann A.);
H. Honour et al. (eds.), The Age of Neoclassicism, exhibition catalogue, London 1972, pp. 106-107, cat. no. 161 (erroneously as Flora instead Silvia and Daphne) and cat. no. 162 (The Nymph of Immortality);
B. Baumgärtel (ed.), in: Angelika Kauffmann 1741–1807. Eine Retrospektive, exhibition catalogue, Düsseldorf 1998, p. 252, cited under cat. no. 120, 121 (as Silvia and Daphne for the first time);
B. Baumgärtel (ed.), in: Angelika Kauffmann - unbekannte Schätze aus Vorarlberger Privatsammlungen, exhibition catalogue, Munich 2019, p. 177 (Silvia), pp. 231-232 (Immortalia)