P. Dejean, Carlo-Rembrandt-Ettore-Jean Bugatti, New York, 1982, p. 166 (another cast of each illustrated).
J.-C. Des Cordes and V. Fromanger, Rembrandt Bugatti: Catalogue raisonné, Paris, 1987, p. 291 (another cast of each illustrated in color).
L. Denys, Rembrandt Bugatti en de Belgische dierensculptuur: 1860-1930, Antwerp, 1990, pp. 79 and 179, no. 97 (mâle).
B. Lamarche-Vadel, B. Dufour and A. Lamparska-Rivet, Bugatti: Les meubles, les sculptures, les autos, Paris, 1995, p. 156 (another cast of the mâle illustrated).
E. Horswell, Rembrandt Bugatti: Life in Sculpture, London, 2004 (another cast of each illustrated in color, p. 200; another cast of the mâle illustrated in color, p. 25).
V. Fromanger, Rembrandt Bugatti, Sculpteur: Répertoire monographique, Paris, 2016, p. 361, no. 290 for the femelle and no. 291 for the mâle (another cast of each illustrated in color, pp. 217 and 361; silver version illustrated in color, p. 361).
E. Horswell, Sculpture of Les Animaliers, 1900-1950, London, 2019, frontispiece (another cast of the mâle illustrated in color).