Catalogue: 2007 Christie's (sales catalogue).
• Sold at auction: Christies, London, Rous Lench collection, May 29-30, 1990, lot 110Book: Fennimore, Donald L., et al. 1992 The David and Peggy Rockefeller Collection: Volume IV Decorative Arts.
• Bow porcelain free-standing white owl of somewhat similar model: p. 90, no. 84, c. 1750-55. This type possibly inspire Winterthur model.