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Credit
The advantages of the Trendelenburg posture during all operations involving directly or indirectly the cavities of the mouth, nose, and the trachea : with a report of two cases of epithelioma and sarcoma of the tonsil / by W.W. Keen. Public Domain Mark. Source: Wellcome Collection.
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This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.