↑J. Ian H. Allonby et Philippe B. Wilson, British poultry standards: complete specifications and judging points of all standardized breeds and varieties of poultry as compiled by the specialist affiliated breed clubs and recognized by the Poultry Club of Great Britain, Wiley Blackwell, (ISBN978-1-119-50919-6, 978-1-119-50917-2 et 978-1-119-50916-5)