Norman Mosley Penzer: The Harem – an account of the institution as it existed in the palace of the Turkish sultans, with a history of the Grand Seraglio from its foundation to the present time. J. B. Lippincott, Philadelphia, Chapter XI, S.246–247 (englisch, Textarchiv – Internet Archive – The Hirka Şerif, or Holy Mantle, am Seitenende).