The attribution is based on a bronze depicting a similar cushion with one King Charles cavalier spaniel signed Lecourtier. It is illustrated in the exhibition catalogue, The Sladmore Gallery, An exhibition of Nineteenth Century Animalier Sculpture, 26th April - 26th May 2006, London, p. 64, cat. nr. 62.
Other casts of the same model -attributed to Antoine Louis Barye- are illustrated in C. Payne, Animals in Bronze, Woodbridge, 1986, p. 227, no. D73 and in S. Pivar, The Barye Bronzes, Woodbridge, 1990, p. 132, no. A31.