The present models are based on George Edwards Natural History of Uncommon Birds, vol. III, pl. 157 where they are described as 'Little Brown and White Ducks'. Another pair, similarly coloured, are in the collection of Temple Newsam House, Leeds. See Anton Gabszewicz, Bow Porcelain, The Collection formed by Geoffrey Freeman, London, 1982, fig. 264.; see also Yvonne Hackenbrock, Chelsea and Other English Porcelain, Pottery and Enamel in the Irwin Untermeyer Collection, London, 1957.