Leighton, R. (1907). The New Book of the Dog; a comprehensive natural history of British dogs and their foreign relatives, with chapters on law, breeding, Kennel Management, and veterinary treatment, by Robert Leighton, assisted by eminent authorities on the various breeds. illustrated with twenty-one coloured plates and numerous photographic portraits of famous dogs. London, UK: Cassell and Co.
Morris, D. (2008). Dogs: The Ultimate Dictionary of Over 1,000 Dog Breeds. North Pomfret, VT: Trafalgar Square.